# Half of you will get this wrong: 48÷2(9+3) = 288 or 2?



## AKIRA (Apr 7, 2011)

Go.

Use properties, use links, use pics.


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## Vick (Apr 7, 2011)

288


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## Zaphod (Apr 7, 2011)

2  Order of operations.


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## Imosted (Apr 7, 2011)

^^^ this 
9+3=12
12*2=24
48/24=2


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## DOMS (Apr 7, 2011)

Zaphod said:


> 2  Order of operations.



Yep.


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## ihateschoolmt (Apr 7, 2011)

I believe 288 because when there are two options like with 48/2x12 you work it left to right. That's what I was taught, and when I tutored algebra that's what I told kids to do so I hope that's right


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## ihateschoolmt (Apr 7, 2011)

Order of Operations
heres a problem with the same dilemma.
[FONT=Verdana, Arial, Helvetica, sans-serif]"20              ÷ (12 - 2) X 32 - 2   [/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]             Everything in the brackets first[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]             20 ÷ 10 X 32 - 2           [/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]Exponents[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]             20 ÷ 10 X 9 - 2           [/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]             Multiply and Divide as they appear[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]             18 - 2                         [/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]Add or Subtract as they appear[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]             16 " (quote from link)

[/FONT]           [FONT=Verdana, Arial, Helvetica, sans-serif]its 288. 

[/FONT]


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## Zaphod (Apr 7, 2011)

Yup.  I was wrong.


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## Curt James (Apr 7, 2011)

It's 17.


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## maniclion (Apr 7, 2011)

Please excuse my dear aunt sally's loud rips...

288


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## KelJu (Apr 7, 2011)

=2

Please Excuse My Dear Aunt Sally


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## ihateschoolmt (Apr 7, 2011)

[FONT=Verdana, Arial, Helvetica, sans-serif]R*ules *

        "1. Calculations must be done from left to right.[/FONT]         [FONT=Verdana, Arial, Helvetica, sans-serif]2. Calculations          in brackets (parenthesis) are done first. When you have more than one          set of brackets, do the inner brackets first.[/FONT]        
 [FONT=Verdana, Arial, Helvetica, sans-serif]3. Exponents          (or radicals) must be done next.[/FONT]        
 [FONT=Verdana, Arial, Helvetica, sans-serif]4. Multiply          and divide in the order the operations occur.[/FONT]       
 [FONT=Verdana, Arial, Helvetica, sans-serif]5. Add and          subtract in the order the operations occur."(same site as I linked before)[/FONT]


 [FONT=Verdana, Arial, Helvetica, sans-serif]multiplying  and dividing have the same value in terms of which goes first, as well  as addition and subtraction. These are worked in the order they appear  when you have the choice.[/FONT]


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## Curt James (Apr 7, 2011)

YouTube Video
















YouTube Video


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## Curt James (Apr 7, 2011)

Three! Ooh! Pick me! Pick me!

Wait. It's 12.

_Nooo_. Don't tell me. *A MILLION!*

_Two million?_


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## jagbender (Apr 7, 2011)

288


48/2 = 24
9+3 12
12 x 24
288


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## KelJu (Apr 7, 2011)

Fuck! I hate being wrong.


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## KelJu (Apr 7, 2011)

But you have to appreciate the beauty of math. Had this been an abstract concept, we would have a 20 page thread on our hands with flames and death threats between the divided groups of twoions and twohundredandeightyeightions.


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## maniclion (Apr 7, 2011)

KelJu said:


> =2
> 
> Please Excuse My Dear Aunt Sally



You're making the mistake of thinking My Dear = Multiply then Divide when the rule is Multiply Or Divide depending on order of appearance from Left to Right...


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## AKIRA (Apr 7, 2011)




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## KelJu (Apr 7, 2011)

maniclion said:


> You're making the mistake of thinking My Dear = Multiply then Divide when the rule is Multiply Or Divide depending on order of appearance from Left to Right...



Well I was spoiled by my TI-92.


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## irish_2003 (Apr 7, 2011)

Imosted said:


> ^^^ this
> 9+3=12
> 12*2=24
> 48/24=2



bingo


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## maniclion (Apr 7, 2011)

KelJu said:


> But you have to appreciate the beauty of math. Had this been an abstract concept, we would have a 20 page thread on our hands with flames and death threats between the divided groups of twoions and twohundredandeightyeightions.


I think problems like this along with my dyslexia caused me to fail Algebra the first time around, because I am such an abstract thinker, I'd confuse myself until a teacher who saw that I could figure out the If, Then, Else & And/Or of computer programming with ease showed me the exact logic....


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## Curt James (Apr 7, 2011)

AKIRA said:


> *48÷2(9+3) =*



That whole order of operations things sounds vaguely familiar. 

But I thought you would do the division thing for 24 then do the addition thing for 12 and _then _multiply 24 and 12 for, uh...

I'm an _art _teacher. I can draw a calculator but don't ask me to _use _one! 

Of course they say that art and math are closely related, so...
*
Mathematics and art - Wikipedia, the free encyclopedia*

Anyway, my vote is for 288.


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## Curt James (Apr 7, 2011)

maniclion said:


> I think problems like this along with my dyslexia *caused me to fail Algebra* the first time around, because I am such an abstract thinker, I'd confuse myself until a teacher who saw that I could figure out the If, Then, Else & And/Or of computer programming with ease showed me the exact logic....



Believe I had a C or D in _pre_-Algebra. Dropped Geometry because I disliked the teacher. 

But gosh darn it, I got an A in illustration!


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## MDR (Apr 7, 2011)

288-and I be an Engllish Teacherr.


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## LAM (Apr 7, 2011)

are you not to assume that 48÷2(9+3) equals (48÷2(9+3)) 

I'm going with 2


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## Built (Apr 7, 2011)

288


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## bulldogz (Apr 7, 2011)

48 ÷ 2(12) = 2


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## danzik17 (Apr 7, 2011)

288.


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## Diesel618 (Apr 7, 2011)

lol @ retarded people.

It's definately 2.


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## Built (Apr 7, 2011)

48÷2(9+3)

See, here's the problem. In order to evaluate the 2(9+3) first, you'd need to have brackets around that part, like this:

48÷[2(9+3)]

Were this the case, the problem would reduce to 
48÷[2(12)]
=48÷[24]
=2

But you don't. Without the [brackets] around 2(9+3), order of operations requires 48 to be divided by two (into 24), and that this result is then multiplied by 12. Hence the 288.


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## danzik17 (Apr 7, 2011)

LAM said:


> are you not to assume that 48÷2(9+3) equals (48÷2(9+3))
> 
> I'm going with 2



Would it help if it was written like 48 / 2 * (9 + 3)?

Division, multiplication, and modulus are weighted equally.


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## Kirk B (Apr 7, 2011)

*288 i promise*

288 PEOPLE


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## Diesel618 (Apr 7, 2011)

it's the same thing as 48/(18+6)


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## bulldogz (Apr 7, 2011)

fvck...it's from left to right...doin what is in parenthesis first...


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## Diesel618 (Apr 7, 2011)

parenthesis first means distribute the 2


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## danzik17 (Apr 7, 2011)

Look, if you don't believe it, copy the following into your address bar and hit enter:

javascript:alert(48/2*(9+3))


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## danzik17 (Apr 7, 2011)

Diesel618 said:


> parenthesis first means distribute the 2



No it doesn't - parenthesis simply affects the order of operations.

Tell me, what is this equal to:

1 * ((48 / 2) * (9 + 3))


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## Diesel618 (Apr 7, 2011)

this is an instance where typing it into your calculator will give you the wrong answer.


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## Diesel618 (Apr 7, 2011)

you have the 2 separated from the addition operation. 2(9+3) = (18+6)


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## MyK (Apr 7, 2011)

LMFAO 

288... bedmas much!?!?!!


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## Triple Threat (Apr 7, 2011)

Diesel618 said:


> this is an instance where typing it into your calculator will give you the wrong answer.



Then either your calculator is busted or you don't know how to use it.


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## bulldogz (Apr 7, 2011)

even if you distribute the 2, you will have 2(9+3) = 18 + 6 = 24

48 ÷ 24 = 2....left to right

10th graders and my high school teacher are laughing at us right now...


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## Diesel618 (Apr 7, 2011)

It's pemdas, but anyways....p stands for parethesis last time i checked. That means you work 2(9+3) first. 

Now I'm startin to think I have the wrong approach. Damn. Fuck all of you.


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## danzik17 (Apr 7, 2011)

bulldogz said:


> even if you distribute the 2, you will have 2(9+3) = 18 + 6 = 24
> 
> 48 ÷ 24 = 2
> 
> 10th graders and my high school teacher are laughing at us right now...



Uh dude this is like....5th grade math =P


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## Diesel618 (Apr 7, 2011)

bulldogz said:


> even if you distribute the 2, you will have 2(9+3) = 18 + 6 = 24
> 
> 48 ÷ 24 = 2
> 
> 10th graders and my high school teacher are laughing at us right now...


 
that's what I was thinking. I worked it out two different ways and got 2 and convinced myself I wasright. Now I want to kill something. I hate getting shit wrong.


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## BillHicksFan (Apr 7, 2011)

I don't practise Yanky math. Where I come from that equals 288.


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## lnvanry (Apr 7, 2011)

2

I fail to see why this is so confusing...Its simple arithmetic


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## danzik17 (Apr 7, 2011)

Diesel618 said:


> It's pemdas, but anyways....p stands for parethesis last time i checked. That means you work 2(9+3) first.
> 
> Now I'm startin to think I have the wrong approach. Damn. Fuck all of you.



The 2 is not contained within the parenthesis, it is not a part of that operation.


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## Diesel618 (Apr 7, 2011)

I'm not stupid! I'm just a bad test taker. lol.


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## bulldogz (Apr 7, 2011)

danzik17 said:


> Uh dude this is like....5th grade math =P


 
lol....werd..!!


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## MyK (Apr 7, 2011)

facepalm.jpg

bedmas... brackets.. division... multiplication.. add.. subtract!!!!

48 / 2(9+3) =
48 / 2(12) =
24(12) =
288


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## bulldogz (Apr 7, 2011)

MyK 3.0 said:


> facepalm.jpg
> 
> bedmas... brackets.. division... multiplication.. add.. subtract!!!!
> 
> ...


 
Your acronym is right, but there are no brackets in this equation...so the correct acronym is pemdas....just sayin


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## MyK (Apr 7, 2011)

bulldogz said:


> Your acronym is right, but there are no brackets in this equation...so the correct acronym is pemdas....just sayin


 
I learnt that shit is England as a small boy. our language, we own it, we use it how the fuck we want. when we are talkin American that you can chirp. just sayin


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## danzik17 (Apr 7, 2011)

How's about a more interesting, yet still easy one.


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## MyK (Apr 7, 2011)

5


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## bulldogz (Apr 7, 2011)

#1. 48 ÷ x(9 + 3) = 2
48 ÷ 9x + 3x = 2
48/12x = 2
4/x = 2
4 = 2x
4/2 = x

or

#2. 48 ÷ x(9 + 3) = 288
48 ÷ 9x + 3x = 288
48/12x = 288
4/x = 288
4 = 288x
4/288 = x
1/72 = x


I go with the number 1....


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## maniclion (Apr 7, 2011)

I just used my calculator and this is what it gave me: 288 as I knew it would because you guys are confusing Multiply OR Divide Add OR Subtract with Multiply THEN Divide....OR is the proper rule and you work it Left to Right, also it's the stuff In parentheses not next to it also.... 


Google Calc rewrites it as thus:
(48 ÷ 2) * (9 + 3) = 288


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## Glycomann (Apr 7, 2011)

I wish I had 2 more balls to laugh right off.


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## MyK (Apr 7, 2011)

Glycomann said:


> I wish I had 2 more balls to laugh right off.


 
you need 1 pair first their cheif


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## ManInBlack (Apr 7, 2011)

its fucking 2!!!!


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## ZECH (Apr 7, 2011)

Built said:


> 48÷2(9+3)
> 
> See, here's the problem. In order to evaluate the 2(9+3) first, you'd need to have brackets around that part, like this:
> 
> ...



Yes^^ Left to right and stuff in parenthesis last.......(FOIL method) First, outside, inside, last)


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## Built (Apr 7, 2011)

ManInBlack said:


> its fucking 2!!!!




No, it really isn't. See my explanation, above.


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## ManInBlack (Apr 7, 2011)

fuck this thread.


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## FitnessBlogger (Apr 7, 2011)

so.. = (48/2)(9+3)

BEDMAS people.. 288.


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## Diesel618 (Apr 7, 2011)

ManInBlack said:


> fuck this thread.


 
and everyone in it.

math tards.

I'd like to see you faggots find your way around a biochem lab.

assholes.


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## BillHicksFan (Apr 7, 2011)

I honestly don't understand the confusion. What is it with you meathead bodybuilders?

I did the shit in my head, it's basic math.


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## MyK (Apr 7, 2011)

Diesel618 said:


> and everyone in it.
> 
> math tards.
> 
> ...


 

lulz.jpg


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## maniclion (Apr 7, 2011)

Diesel618 said:


> and everyone in it.
> 
> math tards.
> 
> ...


Not if you're doing the conversions for measurements, something might slpode....


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## 2B1 (Apr 7, 2011)

Zaphod said:


> 2  Order of operations.





Imosted said:


> ^^^ this
> 9+3=12
> 12*2=24
> 48/24=2





irish_2003 said:


> bingo





bulldogz said:


> 48 ÷ 2(12) = 2





Diesel618 said:


> lol @ retarded people.
> 
> It's definately 2.




me too...


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## bulldogz (Apr 7, 2011)

lol...this is great..peoples are gettin pissed about this...

foil method is only if the equation was written: (48÷2)(9+3)...and actually only if both operation inside the parenthesis are the same...(x+y)(x+y)


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## GearsMcGilf (Apr 7, 2011)

It's 288.  Order of operations nigs!  Multiplication comes before addition and subtraction.  It doesn't matter if you use brackets or not.


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## 2B1 (Apr 7, 2011)

X=48/2(9+3)
=48/(18+6)
=48/24
=2

It's 2.


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## ManInBlack (Apr 7, 2011)

its fucking 2!!!!


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## x~factor (Apr 7, 2011)

It's 288. I should know, I'm Asian. LOL


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## ManInBlack (Apr 7, 2011)

x~factor said:


> It's 288. I should know, I'm Asian. LOL


 
that was pretty funny im not gonna lie, but its still 2


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## ManInBlack (Apr 7, 2011)

OP, where did this math problem come from? it should go back from which it came


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## MyK (Apr 7, 2011)

x~factor said:


> It's 288. I should know, I'm Asian. LOL


 

racists are killing this place!


sad.jpg


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## HialeahChico305 (Apr 7, 2011)

plop.com


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## vortrit (Apr 7, 2011)

Who really cares? Damn, I bet Prince didn't know this place would one day turn into and English and math forum.


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## ManInBlack (Apr 7, 2011)

fuck this thread


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## Bigb21084 (Apr 7, 2011)

Always do what is in the () first... (9+3)= 12... then multiplication goes next 2(12)=24... Thus leaving you with 48/12= two


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## 2B1 (Apr 7, 2011)

ManInBlack said:


> fuck this thread


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## MyK (Apr 7, 2011)

Bigb21084 said:


> Always do what is in the () first... (9+3)= 12... *then multiplication goes next 2(12)=24... Thus leaving you with 48/12=* two


 
division before multiplication!! dumbasss!!!!!!


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## ManInBlack (Apr 7, 2011)




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## ManInBlack (Apr 7, 2011)




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## Bigb21084 (Apr 7, 2011)

It is 288... Alpharam.com


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## Curt James (Apr 7, 2011)

Built said:


> 288



Close thread?



lnvanry said:


> 2
> 
> I fail to see why this is so confusing...Its simple arithmetic



heh

The OP better have the definitive answer!


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## Curt James (Apr 7, 2011)

MyK 3.0 said:


> division before multiplication!! dumbasss!!!!!!



HEY! WATCH IT WITH THE _"DUMBASS"_. 
HE USED THE WORD THUS, PAL! ​


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## AKIRA (Apr 7, 2011)

48÷2(9+3)

Once you add the 9 and the 3 and get 12, its in the parenthesis by itself.  What is left to do inside the parenthesis since you do that first?

(According to "bedmas..")


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## soxmuscle (Apr 7, 2011)

288


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## ihateschoolmt (Apr 7, 2011)

Oh man I left for a while and I can't believe how big this thread got.


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## soxmuscle (Apr 7, 2011)

this is an outrageous thread.  awesome post, akira.


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## 2B1 (Apr 7, 2011)




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## x~factor (Apr 7, 2011)

Bigb21084 said:


> Always do what is in the () first... (9+3)= 12... then multiplication goes next 2(12)=24... Thus leaving you with *48/12= two*



48/12 is FOUR. 

I told you I'm Asian. LOLOL


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## Built (Apr 7, 2011)

2B1 said:


>



Wtf?


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## ihateschoolmt (Apr 7, 2011)

You guys are killing me. Google the answer and then pay me to tutor your kids.


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## Built (Apr 7, 2011)

Seriously. I mean, the "boobs" thread didn't grow this fast.


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## vortrit (Apr 7, 2011)

Built said:


> Seriously. I mean, the "boobs" thread didn't grow this fast.



That's because most IM members (well all of them besides me) are homosexuals who would rather try to solve math problems than look at tits.


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## BillHicksFan (Apr 8, 2011)

vortrit said:


> That's because most IM members (well all of them besides me) are homosexuals who would rather try to solve math problems than look at tits.


 

Yesterday while sitting in the Chiro's waiting room I read that 1 in 20 people claim to be homosexual however the results are more likely to be 1 in 12. 

You may have a point Vortit. Of course these figures would mean nothing to at least half of IM members due to their struggle with mathematics.


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## Triple Threat (Apr 8, 2011)

danzik17 said:


> how's about a more interesting, yet still easy one.



75


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## myCATpowerlifts (Apr 8, 2011)

Diesel618 said:


> lol @ retarded people.
> 
> It's definately 2.



This.

Come on people. It's 2.


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## jagbender (Apr 8, 2011)

Fastest growing thread on IM award goes to  AKIRA


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## hoyle21 (Apr 8, 2011)

48/2(9+3) is the same as (48/2)*(9+3)

As a Math major it is poorly written and an obvious attempt to trick people.

He was right though, half of you got it wrong.


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## myCATpowerlifts (Apr 8, 2011)

How about this:

48
____

2(9+3)


Solution - 2


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## ZECH (Apr 8, 2011)

myCATpowerlifts said:


> How about this:
> 
> 48
> ____
> ...



No....................
















































No


















































And No!


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## ZECH (Apr 8, 2011)

And to think today's youth are tomorrow's leaders......we're in big trouble!


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## REDDOG309 (Apr 8, 2011)

Dis rif matic hard


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## myCATpowerlifts (Apr 8, 2011)

dg806 said:


> And to think today's youth are tomorrow's leaders......we're in big trouble!



OH yea, because TODAY'S leaders are any better


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## ROID (Apr 8, 2011)

Please excuse my dear aunt sally


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## ROID (Apr 8, 2011)

i'll be damn, its 288 or so says my TI89 Titanium gold edition limited


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## maniclion (Apr 8, 2011)

My casio piece of shit work calculator says it's 2, what a dumb ass....


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## ROID (Apr 8, 2011)

my TI 30 says its 4


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## 2B1 (Apr 8, 2011)

hoyle21 said:


> 48/2(9+3) is the same as (48/2)*(9+3)
> 
> As a Math major *it is poorly written and an obvious attempt to trick people.
> *
> He was right though, half of you got it wrong.



math majors...


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## 2B1 (Apr 8, 2011)

It's 2.

_I reject your reality, and substitute my own._


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## dteller1 (Apr 8, 2011)

its 288....and its easy if you use this acronym that i was taught at school.

BIDMAS

Brackets Indices Division Multiplication Addition Subtraction

it goes in order of what you do first so in the example:

48÷2(9+3)

its easier to write 48÷2 X (9+3)

brackets first so (9+3) = 12

next division so 48÷2 = 24

you are left with 24 X 12 = 288


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## myCATpowerlifts (Apr 8, 2011)

no no no. God people. You can't do that. If it were upper level math, you'd start seeing your errors.

It's PEMDAS
Therefore.

(9+3) = 12
2(12)= 24


48
--     =   2
24


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## dteller1 (Apr 8, 2011)

http://maths-wiki.wikispaces.com/Bidmas

Order of Operations - BODMAS

http://www.oceanic.name/mathematics/tiki-download_wiki_attachment.php?attId=362

nope its what i said....


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## myCATpowerlifts (Apr 8, 2011)

I have used PEMDAS all my life.
Never heard of bidmas.

I used it in highschool, on Standardized testing (TAKS)
On SAT's
In college algebra, trig, math for CS majors, physics...
Never had a problem.

PEMDAS is correct.
I don't care about your dumb links.


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## dteller1 (Apr 8, 2011)

PEDMAS is the same ...Parenthesis Exponents Division Multiplication Addition Subtraction just different acronym

BUT if you actually follow it you'll see you are wrong

48÷2(9+3) becomes 48÷2x(9+3)


becomes 48÷2x(12) division and multiplication are equal priority so you read from left to right when signs are equal so...

it becomes 48÷2 first = 24 

and finally x 12 = 288.


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## hoyle21 (Apr 8, 2011)

myCATpowerlifts said:


> no no no. God people. You can't do that. If it were upper level math, you'd start seeing your errors.
> 
> It's PEMDAS
> Therefore.
> ...




Why do you work right to left?   The point to this problem is to show how important communication is.   Both answers are correct, but I would lean towards 288 just because it is done left to right.  There is no rule that says go left to right though.   In fact it is not supposed to matter if multiplication or division is done first, because division is just the multiplication of an inverse.


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## dteller1 (Apr 8, 2011)

actually.... there is a rule that you work from left to right check the links i posted

hell even check this PEDMAS one

Order of Operations - PEMDAS (with worked solutions & videos)

it clearly states you work from left to right

i will quote
"Then, carry out multiplication or division, working from left to right"
straight from the page


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## hoyle21 (Apr 8, 2011)

dteller1 said:


> actually.... there is a rule that you work from left to right check the links i posted
> 
> hell even check this PEDMAS one
> 
> ...




You are right it does say that.   Either way it is a poorly written problem.   Subtraction is nothing more than adding a negative, and division is multiplication of an inverse.  It really "shouldn't" matter.

I still believe the point to the problem is to show how important communication is, not to really get an answer.


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## ZECH (Apr 8, 2011)

myCATpowerlifts said:


> OH yea, because TODAY'S leaders are any better



You got a good point!


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## bulldogz (Apr 8, 2011)

dteller1 said:


> PEDMAS is the same ...Parenthesis Exponents Division Multiplication Addition Subtraction just different acronym
> 
> BUT if you actually follow it you'll see you are wrong
> 
> ...


 
PEMDAS is not the same as BIDMAS....parenthesis and brackets are totally different when it comes to mathematics...

Your equation is incorrect...x12 = 288..?????....you still have to solve for "x" in your equation/explanation...plus you just can’t put "x" where ever you want...”x” has to replace a number within the equation…check out post #57....

http://www.ironmagazineforums.com/2250713-post57.html


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## maniclion (Apr 8, 2011)

hoyle21 said:


> You are right it does say that.   Either way it is a poorly written problem.   Subtraction is nothing more than adding a negative, and division is multiplication of an inverse.  It really "shouldn't" matter.
> 
> I still believe the point to the problem is to show how important communication is, not to really get an answer.


It's a poorly written equation, but there still is a right answer...


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## dteller1 (Apr 8, 2011)

X is a multiplication sign............i didnt think anyone wouldnt understand that....wow


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## troubador (Apr 8, 2011)

If this were a real equation it would be written differently. By real equation I mean like the Bernoulli equation or ideal gas law.


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## hoyle21 (Apr 8, 2011)

http://www.physicsforums.com/showthread.php?t=488334

Even the physics guys are struggling with it.


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## maniclion (Apr 8, 2011)

In other news today, people across the internet have actually been debating on something intellectually stimulating.....that's right MATH and to top it off it seems to have been started at a bodybuilding website....


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## maniclion (Apr 8, 2011)

Wikipedia page on Order of Operations has changed (probably cause of this?), they had links to some Laws of logic and they disappeared, I was going to read them to find a Proof but now I can't find them....

The person who proves this will be kind of famous maybe?


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## danzik17 (Apr 8, 2011)

maniclion said:


> In other news today, people across the internet have actually been debating on something intellectually stimulating.....that's right MATH and to top it off it seems to have been started at a bodybuilding website....



Unfortunately said math is of the 5th grade level, but hey it's a start.


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## maniclion (Apr 8, 2011)

Why is math coming into my life so much lately?  The other night I watched this movie called Fermat's Room and the plot was tied to Goldbach's Conjecture, so I looked it up and got caught up in it, then I watched a show on Discovery about blackholes and looked up the math related to them and now this....it's a conspiracy to drive me more insane I think...






YouTube Video


----------



## maniclion (Apr 8, 2011)

danzik17 said:


> Unfortunately said math is of the 5th grade level, but hey it's a start.


I recall Pre-Algebra in 8th grade, but in 5th?  Maybe in India or China...


----------



## danzik17 (Apr 8, 2011)

maniclion said:


> I recall Pre-Algebra in 8th grade, but in 5th?  Maybe in India or China...



It's just basic order of operations.  When did you go to school?  I remember doing algebra maybe around 7th grade in middle school, though I did skip a couple of the easier classes.


----------



## maniclion (Apr 8, 2011)

danzik17 said:


> It's just basic order of operations.  When did you go to school?  I remember doing algebra maybe around 7th grade in middle school, though I did skip a couple of the easier classes.


Texas public schools Honors classes...


----------



## maxpro2 (Apr 8, 2011)

Google's calculator says 288. 

48÷2(9+3) - Google Search


----------



## hoyle21 (Apr 8, 2011)

maxpro2 said:


> Google's calculator says 288.
> 
> 48÷2(9+3) - Google Search



and google is never wrong.


----------



## Built (Apr 8, 2011)

hoyle21 said:


> *Both answers are correct,*



No, they're not. That's the beauty of mathematics. Right or wrong isn't a matter of opinion; it's a matter of logic. 

You've heard from at least two former math tutors already - me, and ihateschool. 

My first degree was in Mathematics. I broke it down for you earlier in this thread. 

Would this make it easier? 
______________________________________

I'll get rid of the (9+3) by simplifying it down to 12.

Like subtraction, division must not be performed in just any order - barring parentheses, it must be performed from left to right. 

However, multiplication may be performed in any order. 

As correctly noted by others, division by 2 is simply multiplication by its reciprocal, ½:  

Thus48 ÷ 2  ?? 12​becomes48 ?? ½ ?? 12​Which may be evaluated in whatever order you like. For example, this one:
48 ?? 12 ?? ½​
48 ?? 12 = 576, and 576 ?? ½ = 288​
Or this one, if you prefer:
½ ?? 12 ?? 48​
½ ?? 12 = 6, and 6 ?? 48 = 288​


----------



## danzik17 (Apr 8, 2011)

maniclion said:


> Texas public schools Honors classes...



/shrug

I don't know then.  I think it's more the timeframe than where one went.  The math being taught in high school these days is pathetic, playing to the lowest common denominator.  Thanks "No Child Left Behind" a.k.a "No Child Leaps Forward".


----------



## hoyle21 (Apr 8, 2011)

Built said:


> No, they're not. That's the beauty of mathematics. Right or wrong isn't a matter of opinion; it's a matter of logic.
> 
> You've heard from at least two former math tutors already - me, and ihateschool.
> 
> ...


Yeah I worded that wrong.  I have serious issues with the way the  problem is presented.  It is horribly written and nobody in any math or  science field would express that equation in such terms.  Which is why people are getting different answers.  I posted a link to a physics forum where they are also in disagreement.  Physicist are pretty much mathematicians by default.

It really needs to show brackets when doing this.  The divided by sign can also be written as a fraction.  However, the way it is written if you put it in fraction form it would be 48 / 2(9+3) which is clearly 2.

The laws of Algebra and Calculus tell us there should be no problem manipulating that problem, we should get the same answer, but clearly we do not.   It's a bullshit problem, and I still say the point is to prove how important communications is.


----------



## maniclion (Apr 8, 2011)

Built said:


> No, they're not. That's the beauty of mathematics. Right or wrong isn't a matter of opinion; it's a matter of logic.
> 
> You've heard from at least two former math tutors already - me, and ihateschool.
> 
> ...


Oh yeah, well some still think it's 2 so what are you gonna do about that? 

Some are trying to claim there is some Law of Inference that says since the multiplication sign is absent and the 2 is butted up to the () it is inferred it should be done together.....but I have never seen this Law of Inferrence...not even when I learned Programming Languages....


----------



## vortrit (Apr 8, 2011)

Hey math homos!


----------



## hoyle21 (Apr 8, 2011)

maniclion said:


> Oh yeah, well some still think it's 2 so what are you gonna do about that?
> 
> Some are trying to claim there is some Law of Inference that says since the multiplication sign is absent and the 2 is butted up to the () it is inferred it should be done together.....but I have never seen this Law of Inferrence...not even when I learned Programming Languages....




I actually believe, based on the picture of the TI-85 and TI-86 side by side with different answers there may be something to that, but I think it is programming not an official math rule.  I have never heard of such a thing.

I also never heard you had to go from left to right when working a problem.  There should be no difference in the order of subtraction and addition, or multiplication and division.   Another reason this is a bullshit problem.


----------



## Built (Apr 8, 2011)

hoyle21 said:


> Yeah I worded that wrong.  I have serious issues with the way the  problem is presented.  It is horribly written and nobody in any math or  science field would express that equation in such terms.  Which is why people are getting different answers.  I posted a link to a physics forum where they are also in disagreement.  Physicist are pretty much mathematicians by default.
> 
> *It really needs to show brackets when doing this.  The divided by sign can also be written as a fraction.  However, the way it is written if you put it in fraction form it would be 48 / 2(9+3) which is clearly 2.*



The original question was written with a division operator, not a slash:


> 48÷2(9+3)



Exchanging the divisor for a slash isn't enough to turn 2(9+3) into a denominator. In order to do so, it would still require square brackets. Without them, the slash is simply alternative notation to the division operator "÷".

Now, had it been written like this: 
48÷[2(9+3)]​or even like this: 
48/[2(9+3)]​then yes, it would indeed have been equivalent to the fraction below:
.  48  .
2(9+3)​


> The laws of Algebra and Calculus tell us there should be no problem manipulating that problem, we should get the same answer, but clearly we do not.   It's a bullshit problem, and I still say the point is to prove how important communications is.


I didn't concern myself with any interpretation of its purpose. To me, it's just arithmetic.


----------



## Built (Apr 8, 2011)

hoyle21 said:


> I also never heard you had to go from left to right when working a problem.  *There should be no difference in the order of subtraction and addition, or multiplication and division.  *



Really?

So 10 - 7 is the same as 7 - 10? 

How about 100 ÷ 2 and 100 ÷ 2?

Forgot about those, hey? Turns out that while multiplication and addition are open under commutativity, this is not the case for either division or subtraction - for which commutativity is closed.  

I know, it's a bitch, but whaddya gonna do?


----------



## hoyle21 (Apr 8, 2011)

Built said:


> The original question was written with a division operator, not a slash:
> 
> 
> Exchanging the divisor for a slash isn't enough to turn 2(9+3) into a denominator. In order to do so, it would still require square brackets. Without them, the slash is simply alternative notation to the division operator "÷".
> ...




÷, /, and X all represent the same function.
             X 

 1  is the same as 1/2 is the same as 1÷2.  The brackets should be there.
 2

Its a BS problem


----------



## hoyle21 (Apr 8, 2011)

Built said:


> Really?
> 
> So 10 - 7 is the same as 7 - 10?
> 
> ...




no, you are changing the numbers, what Im saying is 6+3-4 =5
                                                                        6-4+3=5

The order doesnt matter as long as the sign stays with the appropriate number.   Same as multiplication and division.

Look I have taken math through Calc, Differential equations, and into Linear Algebra.   I know what Im talking about.   Its a BS problem


----------



## Built (Apr 8, 2011)

hoyle21 said:


> The brackets should be there.


Hmmm... not quite. The brackets COULD be there. 

In order for the answer to be 2, the brackets would have to be there. 

Because they are not, the answer is 288.


----------



## hoyle21 (Apr 8, 2011)

So 10 - 7 is the same as 7 - 10? 

How about 100 ÷ 2 and 100 ÷ 2?

to further illustrate my point, I didnt say the above

10-7 is however is the same as -7+10 (the plus sign in front of the 10 is implied)


----------



## maniclion (Apr 8, 2011)

hoyle21 said:


> I actually believe, based on the picture of the TI-85 and TI-86 side by side with different answers there may be something to that, but I think it is programming not an official math rule.  I have never heard of such a thing.
> 
> I also never heard you had to go from left to right when working a problem.  There should be no difference in the order of subtraction and addition, or multiplication and division.   Another reason this is a bullshit problem.


I think it only proof that when people are taught cute little things like Please Excuse My Dear Aunt Sally they interpret it to mean Multiplication before division and Addition before subtraction....  PEMDAS could be PEDMSA or BEDMSA or BIDMAS


----------



## hoyle21 (Apr 8, 2011)

Built said:


> Hmmm... not quite. The brackets COULD be there.
> 
> In order for the answer to be 2, the brackets would have to be there.
> 
> Because they are not, the answer is 288.




No the brackets should be there in order to solve the problem.  Because someone "could" change it to fraction form and get a completely different answer.   The entire idea of brackets and parenthesis and the order of operations is to stop that from happening.  The division sign has the same function as a fraction bar.


----------



## hoyle21 (Apr 8, 2011)

maniclion said:


> I think it only proof that when people are taught cute little things like Please Excuse My Dear Aunt Sally they interpret it to mean Multiplication before division and Addition before subtraction....  PEMDAS could be PEDMSA or BEDMSA or BIDMAS



Yes it doesnt matter in what order as long as they are grouped.  (addition and subtraction) (multiplication and division)

Im going to just put some random numbers

7+4-6+7-2+9-4-3-7+5=10

You can rearrange that in any order as long you take the number and the sign that is to the left of the number and you still get the same answer. 

*Note that the sign in front of the first 7 is implied to be a +


----------



## Built (Apr 8, 2011)

hoyle21 said:


> no, you are changing the numbers, what Im saying is 6+3-4 =5
> 6-4+3=5
> 
> The order doesnt matter as long as the sign stays with the appropriate number.   Same as multiplication and division.
> ...



I didn't change the numbers - I changed the order of these operations. Without tagging the numbers with their signs, you cannot simply switch them around. 

For instance, 
 6 + 3 = 3 + 6 because both 6 and 3 are both positive; the default notation allows us to assume numbers are positive unless otherwise indicated. 

Meanwhile, 
6 - 3 ≠ 3 - 6, right?​
You have to change the notation to indicate your intention, like this:
6 - 3 = -3 + +6​
When you - with your advanced degree in Teh Math - screwed up simple arithmetic, you made a simple error; the same one, in fact, that I almost made myself. *You assumed notation that would impose a change to the defaults *- only that notation wasn't there. 

Your credentials don't make your error any less wrong.


----------



## hoyle21 (Apr 8, 2011)

Built said:


> I didn't change the numbers - I changed the order of these operations. Without tagging the numbers with their signs, you cannot simply switch them around.
> 
> For instance,
> 6 + 3 = 3 + 6 because both 6 and 3 are both positive; the default notation allows us to assume numbers are positive unless otherwise indicated.
> ...



You changed the numbers.  Changing notation, is changing the number from a positive to a negative.  Which is drastically changing of the number.  Subtraction can also be thought of as adding a negative number.....And so forth. 

Maybe this is just to difficult to get through on the a website.


----------



## hoyle21 (Apr 8, 2011)

Bottom line is 48÷2(9+3) should be the same as 
48  
                                                              2(9+3)

and it isnt.   It is a bad problem.


----------



## Built (Apr 8, 2011)

hoyle21 said:


> You changed the numbers.  Changing notation, is changing the number from a positive to a negative.


And there's the problem. When I switched the positions of the numbers, because of how we use standardized mathematical notation, their signs changed - thus they were no longer the same numbers. 

I, personally, did not change the numbers. Their values changed because I transposed them left and right. 




> Which is drastically changing of the number.


And that was my point with what you did, with the division operator, "÷". You made the assumption that everything following a division operator is handled as if it were in square brackets. 

By (incorrectly) making this assumption, you changed the original statement:
48 ÷ 2(9+3)​to 
48 ÷ 2 ÷ 12​
instead of what the notation actually provides us with, which is this:
48 ÷ 2 ?? 12​
Now I'm sure the notation you learned when you earned your credential was the same notation I learned when I earned mine. Your mind simply tricked you into thinking otherwise, and it's maddening when it's your area.  



> Subtraction can also be thought of as adding a negative number.....And so forth.
> 
> *Maybe this is just to difficult to get through on the a website.*



I didn't think so. But it's interesting to me that you did.


----------



## maniclion (Apr 8, 2011)

No it's the same as 48/2*12 which is the only way my iPhone will let me input division...and multiplication the order of operations stay the same no matter the syntax


----------



## Built (Apr 8, 2011)

hoyle21 said:


> Bottom line is 48÷2(9+3) should be the same as
> 48
> 2(9+3)
> 
> and it isnt.   It is a bad problem.



The bottom line is you fucked up.



			
				Barbie said:
			
		

> Math is tough. Let's go shopping!???


----------



## TheGreatSatan (Apr 8, 2011)

ihateschoolmt said:


> I believe 288 because when there are two options like with 48/2x12 you work it left to right. That's what I was taught, and when I tutored algebra that's what I told kids to do so I hope that's right



Ditto


----------



## vortrit (Apr 8, 2011)

TheGreatSatan said:


> Ditto



Plus if you put it in Google that's the answer you get. Thread closed.


----------



## AKIRA (Apr 8, 2011)

soxmuscle said:


> this is an outrageous thread.  awesome post, akira.


----------



## MyK (Apr 8, 2011)

Built said:


> The bottom line is you fucked up.


 

pwn.jpg


----------



## Curt James (Apr 8, 2011)

Diesel618 said:


> lol @ retarded people.
> 
> It's *definately *2.



Oh, yeah? Oh, _yeah???_

Well, well, well YOU can't even spell _definitely._

So there! *HA!*


----------



## Marat (Apr 8, 2011)

Six pages to argue a math problem that we learn how to solve before we reach puberty....

Another vote for 288:

48÷2(9+3)

1. (9+3) = 12
2. 48÷2 = 24
3. 24 (12) = 288


----------



## Curt James (Apr 8, 2011)

^ Did _you _answer?


----------



## Marat (Apr 8, 2011)

hoyle21 said:


> Bottom line is 48÷2(9+3) should be the same as
> 48
> 2(9+3)
> 
> and it isnt.   It is a bad problem.



(9+3) needs to be raised to the -1 exponent  in order to get the answer to be 2. 

As the problem currently stands, (9+3) will always be in the numerator.

You cannot arbitrarily put 2(9+3) in the denominator due to the order of operations. The division sign applies to the "2", not to "2(9+3)". The question can be read: 48 ÷ 2 x (9+3). 

Perhaps that makes it a bit clearer.


----------



## Marat (Apr 8, 2011)

Curt James said:


> ^ Did _you _answer?



Me? Answer what?


----------



## 2B1 (Apr 8, 2011)

Built said:


> I didn't think so. But it's interesting to me that you did.


----------



## soxmuscle (Apr 9, 2011)

its hard to argue with a calculator...


----------



## soxmuscle (Apr 9, 2011)

...built on the other hand


----------



## NeilPearson (Apr 9, 2011)

I never used an acronym to do math... I used understanding of math to understand what was meant

In this case 48÷2(9+3) clearly is different than 48÷2x(9+3)

with 48÷2(9+3), it is implied to be 48÷[2(9+3)]

If you don't understand this, you missed the basics of math

The answer is 2.  And yes I had top honors in math

Distributive property anyone?


----------



## NeilPearson (Apr 9, 2011)

More than half of them got it wrong... but can you blame them?  It is a body building site.


----------



## Built (Apr 9, 2011)

NeilPearson said:


> In this case 48÷2(9+3) clearly is different than 48÷2x(9+3)
> 
> with 48÷2(9+3), it is implied to be 48÷[2(9+3)]
> 
> If you don't understand this, you missed the basics of math



Oh dear. Is that what you think? 

So, to clarify: You think 2(9+3) ≠ 2??(9+3)?

Really? 

Okay - what's it equal to, then? Or do you somehow imply that alone, this is true:
2(9+3) = 2??(9+3)​
But here, it is not: 48÷2(9+3) ≠ 48÷2??(9+3)​
Is that it? Is that the crux of your argument?


----------



## NeilPearson (Apr 9, 2011)

Marat said:


> (9+3) needs to be raised to the -1 exponent  in order to get the answer to be 2.
> 
> As the problem currently stands, (9+3) will always be in the numerator.
> 
> ...



except that you are wrong.  When you leave the 'x' out between the 2 and the (9+3), the distributive property takes over.  If you had 48÷2b you would write it as

48
__
2b

the same thing happens here. 

48÷2b = 
48 ÷ 2 ÷ b = 
48 ÷ (2 x b)


----------



## NeilPearson (Apr 9, 2011)

Built said:


> Oh dear. Is that what you think?
> 
> So, to clarify: You think 2(9+3) ≠ 2??(9+3)?
> 
> ...



2(9+3) = 2??(9+3) only because there are no other outside operations done to it.  It's not really relevant

a ÷ 2(9+3) ≠ a ÷ 2 ?? (9+3)   ... this is correct


----------



## NeilPearson (Apr 9, 2011)

From Yahoo Answers:

The distributive property of multiplication CLEARLY states that the 2(9+3) is an entire statement and CANNOT be broken up. 2(9+3) follows the distributive property which can be rewritten as (2*9+2*3). Let me repeat the 2 outside of the parenthesis follows the distributive property of multiplication and must be factored and simplified before performing any other operations on it. You do NOT compute this expression from left to right until you use Algebra to simplify the statement 2(9+3).

So this can be rewritten as:
48 / (2*9 + 2*3)

Which leaves us with

48 / 24 = 2

Answer = 2.

Lastly for those using Google or any other online calculator. These do not understand many theorems or properties so you must explicitly explain what you mean. There is a difference between 48 / 2 * (9+3) and 48 / 2(9+3). The first notation reads 48 / 2 * 1(9+3) while the second reads 48 / (2*9+2*3). Be very careful with your signs.


----------



## NeilPearson (Apr 9, 2011)

and yes, I wrote my answer about the distributive property BEFORE looking up the yahoo answers... but I was kind weirded out that that post also used the word "clearly" and mentioned the distributive property in the answer


----------



## NeilPearson (Apr 9, 2011)

Built said:


> Oh dear. Is that what you think?
> 
> So, to clarify: You think 2(9+3) ≠ 2??(9+3)?
> 
> ...




and yes, when you insert the 48 on 48÷2??(9+3), the first thing done is the division because 2??(9+3) isn't as tightly bound as 2(9+3)

adding the 48 on 48÷2(9+3) does not effect the 2(9+3) because the distributive property makes this a single unit that happens before any outside multiplication or division that is otherwise applied


----------



## Marat (Apr 9, 2011)

NeilPearson said:


> except that you are wrong.  When you leave the 'x' out between the 2 and the (9+3), the distributive property takes over.  If you had 48÷2b you would write it as
> 
> 48
> __
> ...




I'm not waiving the white flag yet. 

You are suggesting that:

"48÷2b = 
48 ÷ 2 ÷ b = "


Actually, that is not correct. In the second expression, you are adding a division sign that was not previously there. 48÷2b can be rewritten as (48/2)b or (48/2) x b or (48b)/2 or 48b/2. It cannot be rewritten as 48 ÷ 2 ÷ b. 

Of your original expressions, the third one is simply incorrect -- you are modifying the order of operations by putting in parenthesis that were not expressed originally.

Clearly, the "÷" is an awful convention.


----------



## Marat (Apr 9, 2011)

NeilPearson said:


> a ÷ 2(9+3) ≠ a ÷ 2 ?? (9+3)   ... this is correct



Wait, what? I believe that inequality is false.

a ÷ 2(9+3) = a ÷ 2 ?? (9+3)


----------



## dteller1 (Apr 9, 2011)

NeilPearson said:


> and yes, when you insert the 48 on 48÷2??(9+3), the first thing done is the division because 2??(9+3) isn't as tightly bound as 2(9+3)
> 
> adding the 48 on 48÷2(9+3) does not effect the 2(9+3) because the distributive property makes this a single unit that happens before any outside multiplication or division that is otherwise applied



people have always said that US degree's arent as higher level as other countries and if you got top class honours and you have NO IDEA what you are talking about im starting to agree. 

48÷2(9+3) IS exactly the same as 48÷2 X (9+3), (and for those confused by the X sign its a multiplication, someone was confused earlier in this thread and thought i was solving for x?!)


----------



## hoyle21 (Apr 9, 2011)

I took the time to dig out my old college algebra book after my leg workout this morning, and Built is correct, no i'fs and's or but's.

Because multiplications and division have the same rank, they cannot be broken up in any way, not even with a fraction bar.  The order of operations has to be performed from left to right.

The answer and only answer is 288.


----------



## hoyle21 (Apr 9, 2011)

dteller1 said:


> people have always said that US degree's arent as higher level as other countries and if you got top class honours and you have NO IDEA what you are talking about im starting to agree.




At the high school level correct.  You can put a degree from Northwestern, MIT, Harvard, Yale, Stanford, Michigan, Princeton, etc, against anywhere in the world.


----------



## Built (Apr 9, 2011)

NeilPearson said:


> and yes, when you insert the 48 on 48÷2??(9+3), the first thing done is the division because 2??(9+3)* isn't as tightly bound* as 2(9+3)


"tightly bound"? LMAO this isn't chemistry!


NeilPearson said:


> adding the 48 on 48÷2(9+3) does not effect the 2(9+3)


You meant "affect", not "effect". Oh, and the rest of your statement is wrong, too. 


NeilPearson said:


> because the distributive property makes this a single unit that happens before any outside multiplication or division that is otherwise applied





dteller1 said:


> people have always said that US degree's arent as higher level as other countries and if you got top class honours and you have NO IDEA what you are talking about im starting to agree.


Given some of the posts in here, I'm inclined to agree. 



dteller1 said:


> 48÷2(9+3) IS exactly the same as 48÷2 X (9+3), (and for those confused by the X sign its a multiplication, someone was confused earlier in this thread and thought i was solving for x?!)





hoyle21 said:


> I took the time to dig out my old college algebra book after my leg workout this morning, and Built is correct, no i'fs and's or but's.
> 
> Because multiplications and division have the same rank, they cannot be broken up in any way, not even with a fraction bar.  The order of operations has to be performed from left to right.
> 
> The answer and only answer is 288.


----------



## MyK (Apr 9, 2011)




----------



## hoyle21 (Apr 9, 2011)

MyK 3.0 said:


>




That's funny right there


----------



## ihateschoolmt (Apr 9, 2011)

This thread almost made me and my girlfriend break up


----------



## bulldogz (Apr 9, 2011)

A calulator will always work the problem from left to right...since the calculator is only as good as the person inputting the information

In this problem you will have to break down the parenthesis first, you always do the parenthesis first...always in mathematics...which mean you have to distribute the 2 since the 2 is attached to the parenthesis....which looks like this...

48÷2(9+3)
=48÷(2*9+2*3)
= 48÷(18+6)
= 48÷24
= 2

Always do the parenthesis or what is in or attached to the parenthesis first in math...


----------



## Built (Apr 9, 2011)

ihateschoolmt said:


> This thread almost made me and my girlfriend break up


Hahahaha!


bulldogz said:


> A calulator will always work the problem from left to right...since the calculator is only as good as the person inputting the information


You're half right - it's only as good as the person programming the calculation algorithm, too. Case in point: Excel sometimes comes up with a negative r-squared when you run linear regression. 

Manufacturers of calculators have from time to time tried to come up with more "user-friendly" inputting that ignores the usual rules of math and instead uses what people usually THINK they're asking the machine to deliver. They invariably fail until the user learns to work around these hacks. 

RPN was an approach I very much appreciated - that, plus the inevitable "where's the equal button?" when people asked to borrow your calculator. 


> In this problem you will have to break down the parenthesis first, you always do the parenthesis first...always in mathematics...which mean you have to distribute the 2 since the 2 is attached to the parenthesis....which looks like this...
> 
> 48÷2(9+3)
> =48÷(2*9+2*3)
> ...



Almost. "÷2" is the same as "??½".

Thus
48 ÷ 2(9+3)​becomes
48 ?? ½(9+3)
48 ?? [½(9)+½(3)]
48 ?? (4.5 + 1.5)
48 ?? (6)
= 288​


----------



## jagbender (Apr 9, 2011)

288

This thread is more amusing than any other on the boards   

Throw some politics or religeon in here  for some extra fire!  

Good job Built!


----------



## NeilPearson (Apr 9, 2011)

Marat said:


> I'm not waiving the white flag yet.
> 
> You are suggesting that:
> 
> ...



This is completely incorrect


----------



## NeilPearson (Apr 9, 2011)

dteller1 said:


> people have always said that US degree's arent as higher level as other countries and if you got top class honours and you have NO IDEA what you are talking about im starting to agree.
> 
> 48÷2(9+3) IS exactly the same as 48÷2 X (9+3), (and for those confused by the X sign its a multiplication, someone was confused earlier in this thread and thought i was solving for x?!)



I grew up in Canada


----------



## NeilPearson (Apr 9, 2011)

bulldogz said:


> A calulator will always work the problem from left to right...since the calculator is only as good as the person inputting the information
> 
> In this problem you will have to break down the parenthesis first, you always do the parenthesis first...always in mathematics...which mean you have to distribute the 2 since the 2 is attached to the parenthesis....which looks like this...
> 
> ...



Correct!


----------



## NeilPearson (Apr 9, 2011)

http://www.youtube.com/watch?v=gFKGbU6ARQg&feature=player_embedded


----------



## NeilPearson (Apr 9, 2011)

the notation of 2(a) implies that you have a group of 2 a's

so if you divide by 2(a), you have to view that as a single unit, not dividing by 2 and then multiplying by a

with your logic, does 48 / 2a  = 48 ÷ 2a ?

Is there a difference here?


----------



## soxmuscle (Apr 9, 2011)

well done, myk.


----------



## Built (Apr 9, 2011)

Marat said:


> I'm not waiving the white flag yet.
> 
> You are suggesting that:
> 
> ...


Nope. Marat nailed it. 



dteller1 said:


> people have always said that US degree's arent as higher level as other countries and if you got top class honours and you have NO IDEA what you are talking about im starting to agree.
> 
> 
> NeilPearson said:
> ...



Dammit Neil, you're bringing down the Canadian average.


----------



## myCATpowerlifts (Apr 9, 2011)

dteller1 said:


> PEDMAS is the same ...Parenthesis Exponents Division Multiplication Addition Subtraction just different acronym
> 
> BUT if you actually follow it you'll see you are wrong
> 
> ...



God you're dumb.
the acronym you used is PEDMAS not PEMDAS.

Go back to school wannabe.


----------



## Built (Apr 9, 2011)

NeilPearson said:


> YouTube - 48÷2(9+3) Solution



Cool. Some other person made the same mistake you did. 

I imagine it's nice to take comfort in that.


----------



## NeilPearson (Apr 9, 2011)

Some smart calculators were programed properly and show that there is a difference between these two


----------



## myCATpowerlifts (Apr 9, 2011)

Built said:


> Cool. Some other person made the same mistake you did.
> 
> I imagine it's nice to take comfort in that.



FIRST, Akira, I saw this thread on another board.
Do you attend the joe rogan board also?

SECOND, 

Anyone who thinks it's 288 DOES NOT KNOW MATH.

GO back to school and see if your random method of solving equations gets you very far.

/thread


----------



## NeilPearson (Apr 9, 2011)

Built said:


> Nope. Marat nailed it.
> 
> 
> 
> Dammit Neil, you're bringing down the Canadian average.



I'm sorry you don't understand


----------



## Built (Apr 9, 2011)

LMAO you're adorable Neil. Really you are. 

Still wrong, though.


----------



## myCATpowerlifts (Apr 9, 2011)

Built said:


> LMAO you're adorable Neil. Really you are.
> 
> Still wrong, though.



Someone's PMS'ing hard.

You have a degree right? And you still don't know elementary math operations?


----------



## ihateschoolmt (Apr 9, 2011)




----------



## Built (Apr 9, 2011)

myCATpowerlifts said:


> FIRST, Akira, I saw this thread on another board.
> Do you attend the joe rogan board also?
> 
> SECOND,
> ...


Hahahahahaha I'll inform NSERC you've placed a lien on the graduate scholarship I earned with my math degree.


----------



## Built (Apr 9, 2011)

myCATpowerlifts said:


> Someone's PMS'ing hard.
> 
> You have a degree right? And you still don't know elementary math operations?



I have two science degrees - my first degree is a BSc in math, and my second is a MSc in op log. I earned a national graduate scholarship for my math degree. I tutored algebra and undergraduate calculus and stats, and worked as a teaching assistant for the Faculty of Science while in university. 

You?


----------



## Built (Apr 9, 2011)

myCATpowerlifts said:


> Someone's PMS'ing hard.



Also wrong. You have to bleed to get PMS.


----------



## myCATpowerlifts (Apr 9, 2011)

Built said:


> Hahahahahaha I'll inform NSERC you've placed a lien on the graduate scholarship I earned with my math degree.



Obviously it's not doing much for you, because you still are incorrect.

PEMDAS

/thread


----------



## control101 (Apr 9, 2011)

_Guy on the physics forums said it best in this The general consensus among math people is that "multiplication by juxtaposition" (that is, multiplying by just putting things next to each other, rather than using the "??" sign) indicates that the juxtaposed values must be multiplied together before processing other operations. ' and its absolutely true. Sure we know that there is a multiplication sign in there when it says 2(9+3) but there has to be a distinction that says 2x(9+3) to follow the left to right rule. If the 2 is next to the parenthesis then the operation is generally assumed to be done before solving the other operations. Built you can argue that it is written like this (even though it isnt) 48÷2*(9+3) that it indeed equals 288, but its not. Since the 2 is attached to the parenthesis it's generally assumed that the operation should be done together. All in all comes down to how its written. I understand the point about if it were written like 48÷2*(9+3), but since that attachment to the parenthesis says that operation is to be done together by general consensus. Distributive Property says it all._


rofl. comes down to interpretation of the person who wrote the problem really. Really there should be a second set of parenthesis in there either way, thats why its poorly written. funny tho!


----------



## myCATpowerlifts (Apr 9, 2011)

control101 said:


> Guy on the physics forums said it best in this The general consensus among math people is that "multiplication by juxtaposition" (that is, multiplying by just putting things next to each other, rather than using the "??" sign) indicates that the juxtaposed values must be multiplied together before processing other operations. ' and its absolutely true.  Sure we know that there is a multiplication sign in there when it says 2(9+3) but there has to be a distinction that says 2x(9+3) to follow the left to right rule.  If the 2 is next to the parenthesis then the operation is generally assumed to be done before solving the other operations.  Built you can argue that it is written like this (even though it isnt) 48÷2*(9+3) that it indeed equals 288, but its not.  Since the 2 is attached to the parenthesis it's generally assumed that the operation should be done together.  All in all comes down to how its written.  I understand the point about if it were written like 48÷2*(9+3), but since that attachment to the parenthesis says that operation is to be done together by general consensus.  Distributive Property says it all.


----------



## Built (Apr 9, 2011)

myCATpowerlifts said:


> Obviously it's not doing much for you, because you still are incorrect.
> 
> PEMDAS
> 
> /thread



I'm enjoying a rather delicious thought: posters who could have sworn they were right, gradually coming to the unpleasant realization that they were, in fact, wrong.

Cognitive dissonance is a bitch.


----------



## NeilPearson (Apr 9, 2011)

From searching on the internet, it looks as though there are arguments on both sides of this... and from people that really should understand the math.

Calculators don't agree either.  I blame the "÷" sign.  It is kind of ambiguous in this case.

For everyone I think a ÷ b X c  is straight forward

a / b X c  should mean the same thing 
but should a / bc ?

a / bc gets a little fuzzy.  Whoever wrote this could have easily meant

a
__
bc

which is how I would have wrote it to avoid confusion or

a / (bc)

I think the original statement is obviously poorly written and even people who are well versed in math seem to have different ideas about what is meant by the equation


----------



## NeilPearson (Apr 9, 2011)

Built said:


> I'm enjoying a rather delicious thought: posters who could have sworn they were right, gradually coming to the unpleasant realization that they were, in fact, wrong.
> 
> Cognitive dissonance is a bitch.



So you are finally realizing you are wrong?


----------



## bulldogz (Apr 9, 2011)

Built said:


> Hahahaha!
> 
> 
> Almost. "÷2" is the same as "??½".
> ...


 
lol...you just can't change the first part of the equation from division to mulitiplcation and add brackets later on just to make it work...

If that's the case...lets just add more parenthesis and do it like this: (48÷2)(9+3) <---wrong by the way

You have to do the 2(9+3) first...no ways around this...parenthesis must be done first in math and the 2 is attched to the parenthesis...

Either by first distributing the 2 or adding what's inside the parenthesis and then mulitplying.....2(12) since the number 2 is still attached to the later part of the equation and it is still in parenthesis...the parenthensis will drop once you mulitiply the 2(12), giving you 24...

I see your logic but it does not work that way and if you have a math degree you should know this...


----------



## hoyle21 (Apr 9, 2011)

^^^^^The answer is 288.  Following the rules it's the only answer you can get.    I still say it is poorly written as well.  One set of brackets would make this thread pointless.


----------



## MyK (Apr 9, 2011)




----------



## Marat (Apr 9, 2011)

I think the issue is that the people who answer "2" form a polynomial-type relationship that isn't there.

In the expression " 10/2x " or "5 ÷ 3x "there is an implied parenthesis (that might not be a real term, it probably isn't) between the variable and the number it's associated with. 

I think Built touched on this, but the expression "3x" means 3 multiplied x times. It implies that there is a parenthesis around "3x", it is implied that it is read "(3x)". The variable introduces a relationship that isn't present in the original 48/2(9+3) expression.

In our original expression, there is no variable that presents an implied parenthesis. Therefore, the normal order of operations needs to be followed.

For example, f(x) = 5/2x  ;;;  does f(10) =  25 or 0.25?

I say that it equals 0.25 because you are implying that there are two 10's that first find themselves in the denominator, before dividing up the "5" that is in the numerator. 

f(x) = 5/2x = 5/(2x) 
f(10) = 5 / (2x10)
        = 5/20
        = 0.25

If we were ignoring that there is a variable involved, and simply going with the expression "5÷2(10)", then we would have to follow the order of operations. First, we'd dividing 5 by 2. That would be 2.5. Then would we multiply by 10. That would be 25. 

However, because of the variable, we first multiply 2 x 10. That equals 20. Then we divide 5 by 20. That equals 0.25.


This analogy applies directly to our original expression.


----------



## Built (Apr 9, 2011)

bulldogz said:


> You have to do the 2(9+3) first...no ways around this...parenthesis must be done first in math and the 2 is attched to the parenthesis...


 
Almost. 

Calculations are performed from left to right, with multiplication and division taking priority over addition and subtraction.  

For example:

3 x 5 + 8 ÷ 4 - 2
Here, because there are no parentheses to tell you otherwise, when parsing from left to right, multiplication and division are performed before addition and subtraction. Here, underlines indicate these groupings:
3 x 5 + 8 ÷ 4 - 2​
and the calculation becomes
15 + 2 - 2 = 15​
Parentheses may be used to deliberately change this order. For example:
3 x 5 + 8 ÷ (4 - 2)​I will again illustrate with underlines
3 x 5 + 8 ÷ (4 - 2)​
The (4 - 2) is calculated first, and we get
15 + 8 ÷ 2
15 + 4
19​


bulldogz said:


> If that's the case...lets just add more parenthesis and do it like this: (48÷2)(9+3) <---wrong by the way



Actually this is right, because here they don't change the default order of operations. Superfluous brackets aren't wrong; they're just messy notation.

Now here, it would be wrong:
48-2(9+3)
(48-2)(9+3)


----------



## Built (Apr 9, 2011)

Marat said:


> I think the issue is that the people who answer "2" form a polynomial-type relationship that isn't there.
> 
> In the expression " 10/2x " or "5 ÷ 3x "there is an implied parenthesis (that might not be a real term, it probably isn't) between the variable and the number it's associated with.
> 
> ...



Marat, I appreciate the support, but using x just means there is no need for the multiplication operator, just like there is no need for one when using parenthesis:

3y = 3 = 3 ?? y

The function you describe,
f(x) = 5/2x​could be written  
f(x) = 2.5x​That is to say, it is linear, with a slope of 2.5

Had it been written thus,
f(x) = 5/(2x)​it would have been a reciprocal function with an odd asymptote at 0.


----------



## Marat (Apr 9, 2011)

oh yea


----------



## Marat (Apr 9, 2011)

lol i had a math epiphany so i'm going to wave the white flag now.


----------



## Built (Apr 9, 2011)

LOL - happens to the best, my friend. You're still my go-to guy for citric acid cycling.


----------



## myCATpowerlifts (Apr 9, 2011)

Built said:


> I'm enjoying a rather delicious thought: posters who could have sworn they were right, gradually coming to the unpleasant realization that they were, in fact, wrong.
> 
> Cognitive dissonance is a bitch.



Thus proving, the ages old addage, that _women_ should stick to reading and writing, and let *men* take care of the math/science.


----------



## bulldogz (Apr 9, 2011)

Yes from left to right, but when parenthesis are invloved you have to, have to do the parenthesis first (meaning get rid of or drop the parenthesis)...the only way to drop the parenthesis is to do the opertation 2(9+6) first...giving you 2(12)....

Since the parenthesis are still incorporated in the equation you must do the multiplication of 2(12)....in other words 2 x 12 to get rid of the parenthesis....then you do left to right...

I'm gonna ask my cousin who's an algebra teacher at our local high school....lol...


----------



## hoyle21 (Apr 9, 2011)

And some are confused about the distributive property.


----------



## bulldogz (Apr 9, 2011)

hoyle21 said:


> And some are confused about the distributive property.


 
Either way works...
2(9+3)
=2(12)
=24

OR

2(9+3)
=(2*9+2*3)
=18+6 <--since we distrubited the 2 the parenthesis drop off the equation
=24


----------



## maniclion (Apr 9, 2011)

If you guys are going to distribute you still have to work left to right so the division would come first....
48/2=24

so now the problem is 24(9+3)
(24*9)(24*3) = 216+72 

216+72= 288

Huh-zah, you are welcome....


----------



## myCATpowerlifts (Apr 9, 2011)

(2b+1d) x (2t+1p)=j


IF:
b=balls
d=dick
t=tit
p=pussy
j=?


----------



## maniclion (Apr 9, 2011)

myCATpowerlifts said:


> (2b+1d) x (2t+1p)=j
> 
> 
> IF:
> ...


J=mycatpowerlifts in a baby carriage....


----------



## ManInBlack (Apr 9, 2011)




----------



## Curt James (Apr 9, 2011)

http://forum.grasscity.com/members/170697-agalloch.html^ lulz

"Let's put it this way

48÷2(9+3) written this way = 48÷[2(9+3)] 

48÷2(9+3) does not = (48÷2)*(9+3) 

48÷2(9+3) 

The 2 and the (9+3) are adjacent, implying multiplication. Whoever wrote this equation did it to FUCK with people lol."

Agalloch @ *48÷2(9+3) = ???? - Page 41 - Grasscity.com Forums*


----------



## Curt James (Apr 9, 2011)

Agalloch's thread was closed, btw. lol

I believe the bb.com thread was closed, too.

_Quitters._ 

"Well a lot of the confusion has arisen because there was no context  behind the question. Some people have assumed that everything after the  "/" sign was intended to be a denominator, while it seems that is  generally not a safe conclusion to draw when you're strictly following  the order of operations. 

The primary argument as to why it was  "2" is that the 2 next to the (9+3) was somehow "attached" to the (9+3).  My argument is that the "48/" is equally attached to the (9+3) since  there is no +, -, or () to separate it, and that you cannot distribute  the 2 through the (9+3) without distributing it as (48/2)*(9+3). 

Your  answer makes sense to me, and I can see why it may be confusing. But I  think if you strictly follow what the order of operations dictate, then  288 would be correct."
sanchito9999 @ *Free Math Help.com - Homework Help! • View topic - Order of Operations - Need Help! Huge Debate!*

And: 

"I get 288. In the acronym PEMDAS, the M and D operations are at the same  priority and the A and S are at the same priority. Arithmetic  operations at the same priority are evaluated left to right. So for  example, 2 + 5 - 3 is the same as (2 + 5) - 3 = 7 - 3 = 4, while 2 - 5 +  3 is the same as (2 - 5) + 3 = -3 + 3 = 0.

I can't say that I remember my algebra teacher in ninth grade going into  quite such detail (in fact, all I remember her telling us was the  acronym MDAS, with a mnemonic device of My Dear Aunt Sally), but  programming languages such as C, C++, C#, Fortran, Pascal, and others  are very specific about operator precedence.

For this reason, 48÷2*(12) should be evaluated as if it were written (48÷2)*12 = 24 * 12 = 288.

If you really meant 






it should be written as 48/(2(9 + 3)). That forces the multiplication to be performed before the division." 
Mark44 @ *48÷2(9+3)*


----------



## Curt James (Apr 9, 2011)




----------



## maniclion (Apr 9, 2011)

I have been looking at the diversity of forums tackling this issue...bodybuilding, physics, rap, gamers, baseball fans, etc... Fascinating indeed!


----------



## B-Cubed (Apr 9, 2011)

My very good friend, Built, brought this thread to my attention.  It's had me in stitches for over an hour now!

My I present my qualifications for answering this question definitively:
A B.S. in Applied Mathematics
A M.S. in Applied Mathematics
A Ph.D. in Applied Mathematics
A 2-year post doctoral fellowship in Mathematics and Earth and Atmospheric Sciences.
My position as an Assistant Professor of Mathematics for nearly 4 years now.

If you will accept my qualifications for answering this question, I'm ready to end the discussion once and for all and put an end to your misery.

Any takers?


----------



## Curt James (Apr 9, 2011)

^ Shoot. But it seems like it's a semantic riddle more than a math problem. And it's obviously been designed to drive us all insane.


----------



## B-Cubed (Apr 9, 2011)

Curt James said:


> ^ Shoot. But it seems like it's a semantic riddle more than a math problem. And it's obviously been designed to drive us all insane.



There is no riddle.  One of the beauties of mathematics is that there is no room for interpretation; there is one, and only one correct interpretation. Therefore, only answer is correct.  Period.  This isn't a political science paper where you score points for arguing your point well.  You are either right or wrong.  I find absolutely nothing ambiguous in the statement of the problem.

Despite what the math major (who shouldn't be getting a degree any time soon) said earlier, problems are, in fact, worked from left to right - the same way we *read*.

As for all of you relying on calculators, let me say this - computers are STUPID.  Technology gets it wrong all too OFTEN - for a myriad of reasons, not the least of which consists of poor programming and the fact that they operate on a subset of the real number line having measure zero, but mostly due to USER ERROR.  Computers are only as smart as the people using them.

Once and for all:  48/2(9+3) = 24(12) = 288.


----------



## Built (Apr 9, 2011)

God bless you.


----------



## ihateschoolmt (Apr 9, 2011)

B-Cubed said:


> There is no riddle.  One of the beauties of mathematics is that there is no room for interpretation; there is one, and only one correct interpretation. Therefore, only answer is correct.  Period.  This isn't a political science paper where you score points for arguing your point well.  You are either right or wrong.  I find absolutely nothing ambiguous in the statement of the problem.
> 
> Despite what the math major (who shouldn't be getting a degree any time soon) said earlier, problems are, in fact, worked from left to right - the same way we *read*.
> 
> ...


  .


----------



## Built (Apr 10, 2011)

kelju said:


> but you have to appreciate the beauty of math. Had this been an abstract concept, we would have a 20 page thread on our hands with flames and death threats between the divided groups of twoions and twohundredandeightyeightions.


Gotta hand it to you, bud - you were closer to the truth than you could have imagined.


----------



## bulldogz (Apr 10, 2011)

Is it this...??

_48_ 
2(9+3)


----------



## Built (Apr 10, 2011)

bulldogz said:


> Is it this...??
> 
> _48_
> 2(9+3)


No.


----------



## Gissurjon (Apr 10, 2011)

dteller1 said:


> PEDMAS is the same ...Parenthesis Exponents Division Multiplication Addition Subtraction just different acronym
> 
> BUT if you actually follow it you'll see you are wrong
> 
> ...


 
as far as i know this is correct, why would you do 2x12 before you would do 48/2 ?? 

Thats how its tought in my school so if its wrong, the educational system is in deeper shit than i thought


----------



## buff1 (Apr 10, 2011)

Built said:


> No.



correct!


----------



## jagbender (Apr 10, 2011)

B-Cubed said:


> There is no riddle. One of the beauties of mathematics is that there is no room for interpretation; there is one, and only one correct interpretation. Therefore, only answer is correct. Period. This isn't a political science paper where you score points for arguing your point well. You are either right or wrong. I find absolutely nothing ambiguous in the statement of the problem.
> 
> Despite what the math major (who shouldn't be getting a degree any time soon) said earlier, problems are, in fact, worked from left to right - the same way we *read*.
> 
> ...


----------



## malfeasance (Apr 10, 2011)

bulldogz said:


> Is it this...??
> 
> _48_
> 2(9+3)


 

Yes.


----------



## malfeasance (Apr 10, 2011)

Half of us will get it wrong?  You pessimist!  How about half of us will get it right!


----------



## dteller1 (Apr 10, 2011)

myCATpowerlifts said:


> God you're dumb.
> the acronym you used is PEDMAS not PEMDAS.
> 
> Go back to school wannabe.



the funny thing is.... that division and multiplication are of equal magnitude and so are addition and substitution equal to each other so you could technically use PEDMSA and it would still be right, remember we work from left to right when the operation is of equal order so as long as in the acronym division and multiplication are 3rd and 4th it doesnt matter which one is 3rd and which is 4th just the same as addition and subtraction being 5th and 6th


----------



## ManInBlack (Apr 10, 2011)




----------



## MyK (Apr 11, 2011)

ManInBlack said:


>


----------



## ManInBlack (Apr 11, 2011)

MyK 3.0 said:


>


----------



## maniclion (Apr 11, 2011)

I think the worst culprit was the distribution method people kept getting confused with, mistaking it as being part of the parentheses first, but if using that method it counts as just Multiplication thus the division has to be done first by the left to right rule....


----------



## MyK (Apr 11, 2011)

ManInBlack said:


>


----------



## dgp (Apr 11, 2011)

*Order of operation*


*Parentheses and Brackets* -- Simplify the inside of parentheses and brackets before you deal with the exponent (if any) of the set of parentheses or remove the parentheses.
*Exponents* -- Simplify the exponent of a number or of a set of parentheses before you multiply, divide, add, or subtract it.
*Multiplication and Division* -- Simplify multiplication and division in the order that they appear from left to right.
*Addition and Subtraction* -- Simplify addition and subtraction in the order that they appear from left to right.
answer =2


----------



## JCBourne (Apr 11, 2011)

Imosted said:


> ^^^ this
> 9+3=12
> 12*2=24
> 48/24=2



This. Order of operations as many have said.


----------



## Built (Apr 11, 2011)

Oh dear, did you miss the memo? A professor of mathematics dropped by and offered her authority in the matter of fifth grade math. 

I am utterly stunned at the level of innumeracy in this thread. If you spelled a word wrong, and someone with an English degree said,  "that's wrong" - you'd take the hit, right?

I have had men on this and other boards ask me for help with training -  especially diet; recently gear; I have no qualifications whatsoever in any of these fields and yet, I have read enough on my own to have earned some respect from at least a few of you. 

I have two science degrees in applied mathematics. I taught math all the way through both degrees. I earned a national scholarship because my grades were so high. I work in an economics unit and build Access and Excel applications for work off the side of my desk, while I'm doing research and writing up analyses. I know WAY more about math than I know about physical culture - and yet, when I DARED to question your authority, I received INSULTS on this thread; I had a man accuse me of PMS-ing; another who told me to leave science for the menfolk. Now I realize this is in fun but MEN don't get to do that; not yet. It's like the n-word; Anybody else says it, it stings like a whip. I'm white and Canadian and even I can see this. 

I'll explain where I am coming from:

I wasn't allowed to take grade 12 math when I wanted to. I got through grades 10 and 11 math when I was in grade ten, earning a nearly 100% average in grade eleven algebra. I wanted to take grade 12 math the next year. 

You know what I was ALLOWED to take? Typing.

And some dorky made-up science class called Human Biology where you just basically had to show up to get an A. Oh, and grade 12 geometry. Interestingly, they couldn't keep me out of Electronics. I was the first girl ever to take electronics at Magee high school. Took it through grade 11. It was just like physics, only easier and more fun. 

Still though, these weren't the courses I wanted to take. They were just fluffy little courses. I got so bored in school after that I just quit. 

I went back to school at 25 when my first husband left, and finished high school. I was really poor; I kept running out of money; I waited tables and worked in a warehouse, did room service Sunday nights at the Hotel Georgia in Vancouver but I kept going. Then I started teaching math - that paid WAY better, so I dropped everything else and just tutored. 

All told, it took me me ten years of plugging away at it a few courses at a time, working a semester or two, then another few courses but I just kept at it - and earned a BSc in math. I took my credential in statistics, and earned a $35,000 scholarship for my grades and planned research. I had two universities fighting over me to go to grad school; I sadly followed the money but that's a different story. I completed a graduate degree and defended a thesis in operations research. 

I mean really - I live through all that, explain, in detail, over numerous posts, the underpinnings of number theory - and I'm told I'm a stupid woman who needs to concede her "error", take Midol, and go cry somewhere. 

Later, a math professor dropped by and blinded you with science - still, I see these posts:


dgp said:


> *Order of operation*
> 
> 
> *Parentheses and Brackets* -- Simplify the inside of parentheses and brackets before you deal with the exponent (if any) of the set of parentheses or remove the parentheses.
> ...





GymRat707 said:


> This. Order of operations as many have said.



How can you not be ashamed to be so innumerate? People are ashamed when they're illiterate; I feel so sorry for people who haven't had the opportunity to learn how to read. 

But the rest of you. I'm beginning to wonder if they teach this stuff at all anymore. 

To all you gear-users out there: I hope you dose better than you compute. 

I'll give you four good reasons:

T3 
clen 
DNP
insulin

Stay safe, hear?


----------



## maniclion (Apr 11, 2011)

Built said:


> Oh dear, did you miss the memo? A professor of mathematics dropped by and offered her authority in the matter of fifth grade math.
> 
> I am utterly stunned at the level of innumeracy in this thread. If you spelled a word wrong, and someone with an English degree said,  "that's wrong" - you'd take the hit, right?
> 
> ...


I failed Algebra my first time around and still knew why it could only be 288...I think I benefit from a job that forces me to make calculations everyday, a little Ohms Law, a bit of trig to find the length of tilt legs for a flat roof mounted system tilted 30 degrees to the south, a bit of just about all the math I learned up to my associates degree.

This thread is a good case to show kids in school how they might "need this" one day in their future....


----------



## ManInBlack (Apr 11, 2011)

MyK 3.0 said:


>


----------



## MyK (Apr 11, 2011)

ManInBlack said:


>


----------



## NeilPearson (Apr 11, 2011)

myCATpowerlifts said:


> Thus proving, the ages old addage, that _women_ should stick to reading and writing, and let *men* take care of the math/science.



Yup I sense a girl brain


----------



## ManInBlack (Apr 11, 2011)

MyK 3.0 said:


>


----------



## NeilPearson (Apr 11, 2011)

The fact is, if the writer meant it to be (48/2)(3+9), they would have wrote it as 48(3+9)/2 or as (48/2)(3+9).

the form a/2b is generally meant to mean a/(2b)...  if that isn't what you meant you would simply write it as ab/2.  Writing it any other way is just mathematically retarded.  Reading a/2b as ab/2 just shows that you can regurgitate an acronym and take it so literally that you screw up what was meant by the person writing the equation.


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## 2B1 (Apr 11, 2011)

so it's 2, right?


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## Jakeyboy696 (Apr 12, 2011)

What is math?


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## manbag83 (Apr 12, 2011)

48÷2(9+3)

1. 48 ÷ 2 x 12  (the parenthesis disappear after they are no longer needed)
2. 24 x 12= 288

This is what my fundamentals tell me!


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## malfeasance (Apr 12, 2011)

bulldogz said:


> _48_
> 2(9+3)


  My mind converts it instantly to this, and, after reading all of the explanations from those who think it is 288, including those explanations from people with multiple math degrees, I still fail to see how it can possibly be what you are claiming. It would need to be expressed differently.

NeilPearson makes a good point:


> The fact is, if the writer meant it to be (48/2)(3+9), they would have wr[itten] it as 48(3+9)/2 or as (48/2)(3+9).
> the form a/2b is generally meant to mean a/(2b)... if that isn't what you meant you would simply write it as ab/2. Writing it any other way is just mathematically retarded.


----------



## B-Cubed (Apr 12, 2011)

This thing is still alive?  I have to admit, I'm kind of appalled.

You've had two people with multiple degrees in mathematics tell you that 1) the question is not ambiguous and that 2) the answer is 288, and there are still posts like this:



NeilPearson said:


> The fact is, if the writer meant it to be (48/2)(3+9), they would have wrote it as 48(3+9)/2 or as (48/2)(3+9).
> 
> the form a/2b is generally meant to mean a/(2b)...  if that isn't what you meant you would simply write it as ab/2.  Writing it any other way is just mathematically retarded.  Reading a/2b as ab/2 just shows that you can regurgitate an acronym and take it so literally that you screw up what was meant by the person writing the equation.



Let me break this down for you. a/2b means (a/2)*b. Period. If one means to write a/(2b) then it is written a/(2b).

It is not "mathematically retarded" that a/2b = ab/2. This is simply a FACT. Whether you like it or not has no bearing whatsoever on its truth.

If the person who wrote the problem did, in fact, mean a/(2b), then they are the one who is guilty of making an error for not writing it so.

There is no room for "interpretation" here. It is not the job of the mathematician to assume to know the mind of the person who poses the question.



malfeasance said:


> My mind converts it instantly to this, and, after reading all of the explanations from those who think it is 288, including those explanations from people with multiple math degrees, I still fail to see how it can possibly be what you are claiming. It would need to be expressed differently.
> 
> NeilPearson makes a good point:



The fact that your mind converts it to one form or another doesn't constitute an argument for that being correct.  The fact that you fail to see the correctness of the multiple arguments Built has given you has no bearing on the correctness of those arguments nor does it imply that the problem needs to be written differently. All you've said here is that you are incapable of recognizing a correct argument.


----------



## myCATpowerlifts (Apr 12, 2011)




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## NeilPearson (Apr 12, 2011)

B-Cubed said:


> This thing is still alive?  I have to admit, I'm kind of appalled.
> 
> You've had two people with multiple degrees in mathematics tell you
> 
> .



... yes but they both have girl brains


----------



## 2B1 (Apr 12, 2011)

B-Cubed said:


> It is not "mathematically retarded" that a/2b = ab/2. This is simply a FACT.




Would you mind, terribly, elucidating this _fact_ for me?


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## NeilPearson (Apr 12, 2011)

These equations were from http://www.chemie.fu-berlin.de/chemistry/general/si_en.html  The 288 guys should tell them them have all their units wrong.

Electric potential
volt: V = W/A = m2 kg/s3 A

Capacitance
farad: F = C/V = s4 A2/m2 kg

Electric resistance
ohm: Omega = V/A = m2 kg/s3 A2

Conductance
siemens: S = A/V = s3 A2/m2 kg

Magnetic flux
weber: Wb = V s = m2 kg/s2 A

Magnetic flux density, magnetic induction
tesla: T = Wb/m2 = kg/s2 A

Inductance
henry: H = Wb/A = m2 kg/s2 A2

Dynamic viscosity
pascal second: Pa s = kg/m s

Heat capacity, entropy
joule per kelvin: J/K = m2 kg/s2 K

Specific heat capacity, specific entropy
joule per kilogram kelvin: J/kg K = m2/s2 K

Thermal conductivity
watt per metre kelvin: W/m K = m kg/s3 K

Energy density
joule per cubic metre: J/m3 = kg/m s2

Electric field strength
volt per metre: V/m = m kg/s3 A


These guys also are guilty of the same:
http://www.goldstandard-mcat.com/physics-equation-lists/

These guys also do the same for Universal gravitational constant
http://www.collegeboard.com/prod_downloads/ap/students/physics/physics_equation_tables.pdf

Physics Guys Just Must Not Understand Math


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## myCATpowerlifts (Apr 12, 2011)

NeilPearson said:


> These equations were from SI Units  The 288 guys should tell them them have all their units wrong.
> 
> Electric potential
> volt: V = W/A = m2 kg/s3 A
> ...


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## NeilPearson (Apr 12, 2011)

B-Cubed said:


> It is not "mathematically retarded" that a/2b = ab/2. This is simply a FACT. Whether you like it or not has no bearing whatsoever on its truth.
> .



Now that's really pushing it...

I could understand if you said a/2 b = ab/2 since it is less clear if the b is written in the denominator or beside the a/2.   a/2b just really looks like it is intended to be under the line.

Math isn't ambiguous.  When written out by hand like it has been for centuries, it is much more obvious if its under the line or beside a fraction.  With ASCII computer notation, sometimes the meaning isn't as obvious.


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## B-Cubed (Apr 12, 2011)

NeilPearson said:


> Now that's really pushing it...
> 
> I could understand if you said a/2 b = ab/2 since it is less clear if the b is written in the denominator or beside the a/2.   a/2b just really looks like it is intended to be under the line.
> 
> Math isn't ambiguous.  When written out by hand like it has been for centuries, it is much more obvious if its under the line or beside a fraction.  With ASCII computer notation, sometimes the meaning isn't as obvious.



Why is that "pushing it?"  It makes it sound like your ego is very attached to being right. Further, your need to rely on irrelevant sexist remarks about women not being able to do math to bolster your position is further evidence that your argument is spurious.

On the other hand, I don't need to call you names or resort to insults. My ego is completely unattached to whether or not you can recognize a correct mathematical argument or not.  Mathematics is totally impartial.

It doesn't matter what it "looks like." Operations proceed from left to right with multiplication and division having the same level of precedence.  This means that a is divided by the 2 first and the result of that operation is multiplied by b, hence a/2b=(a/2)xb.


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## B-Cubed (Apr 12, 2011)

Built, I actually find this rather fascinating as it come up in discussions with my colleagues all the time.  The question is, how do we, as educators, get our students to let go of their incorrect preconceived notions about mathematics (or physics or any hard science).  There are many studies out there that documenting how difficult it is to do. Many students (not all), when presented with concrete arguments or evidence contrary to their beliefs, momentarily give up those beliefs, but revert back to them soon after.

This thread seems like evidence that they never really give up those beliefs at all.  I'm sure that if the people here were paying for a class of mine would give up the goat and say yes Dr. T, you're right, but not because they believe me or have seen the error in their logic, but because I'm the one who assigns them a grade.  I have students in my Calculus class that still don't understand how I can turn 1/2/2 into 1/4. I've been doing it long enough now that it shouldn't surprise me any more, but you know, it kind of does.

I blame acronyms.  How many instances are there in this thread of people reciting some acronym for the order of operations and then go right on to apply it incorrectly? I swear, acronyms are the bane of my existence. Kids memorize acronyms and years later they remember the acronym but not what it means.  It's like the acronym strips all the meaning and understanding of why from the problem.

For me, this whole thread just reinforces the importance of K-6 education.  It seems like if the wires get crossed at that age, they just go blithely through life with all of these misunderstandings, thinking the people with Master's and PhD's are the ones that have it wrong.


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## DOMS (Apr 12, 2011)

This looks like a good place to post this:


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## Built (Apr 12, 2011)

Thank you DOMS.  I agree.


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## myCATpowerlifts (Apr 12, 2011)

B-Cubed said:


> Why is that "pushing it?"  It makes it sound like your ego is very attached to being right. Further, your need to rely on irrelevant sexist remarks about women not being able to do math to bolster your position is further evidence that your argument is spurious.
> 
> On the other hand, I don't need to call you names or resort to insults. My ego is completely unattached to whether or not you can recognize a correct mathematical argument or not.  Mathematics is totally impartial.
> 
> It doesn't matter what it "looks like." Operations proceed from left to right with multiplication and division having the same level of precedence.  This means that a is divided by the 2 first and the result of that operation is multiplied by b, hence a/2b=(a/2)xb.



What's your ego and where is it located?


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## DOMS (Apr 12, 2011)

Built said:


> Thank you DOMS.  I agree.





We all _have _to agree. You heard KelJu, math is purely objective.


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## Built (Apr 12, 2011)

Oh - I see what you did here - you began the list of SI Derived units partway down, *so you wouldn't have to include the instruction that Freie Universität Berlin posted at the top to indicate they were breaking from convention*, presumably for the sake of typographic brevity. 

I'll fix that for you here: 

_______________________________________________
*SI Derived Units

(Please note: all units to the right of the slash are actually in the denominator!)*

Frequency
    hertz: Hz = 1/s

Force
    newton: N = m kg/s2

Pressure, stress
    pascal: Pa = N/m2 = kg/m s2

Energy, work, quantity of heat
    joule: J = N m = m2 kg/s2

Power, radiant flux
    watt: W = J/s = m2 kg/s3

Quantity of electricity, electric charge
    coulomb: C = s A

Electric potential
    volt: V = W/A = m2 kg/s3 A

Capacitance
    farad: F = C/V = s4 A2/m2 kg

(and so on)




NeilPearson said:


> These equations were from SI Units  The 288 guys should tell them them have all their units wrong.
> 
> Electric potential
> volt: V = W/A = m2 kg/s3 A
> ...


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## patricio (Apr 12, 2011)

"The general consensus among math people is that "multiplication by juxtaposition" (that is, multiplying by just putting things next to each other, rather than using the "??" sign) indicates that the juxtaposed values must be multiplied together before processing other operations"
http://www.purplemath.com/modules/orderops2.htm
Even though math is an exact science, there are habits or uses in every science, where people tend to do the same thing when presented to the same problem, just to avoid interpretation. 
Just my two centd


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## hoyle21 (Apr 12, 2011)

I cant believe this is still going.  Built and her friend are 100% correct.  I dont even know why "multiplication by juxtaposition" is being brought up.  You work from left to right when the signs have the same rank.  It is something that either I forgot, or simply had a major brain fart on.  Hell, maybe I was having a bad day and never learned it.   I will say it is very rare that this issue (working left to right) comes up.  It is a secondary rule, but a rule nonetheless.

Work out some other problems  in the same style on your own and you will see why.


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## B-Cubed (Apr 12, 2011)

Built said:


> Oh - I see what you did here - you began the list of SI Derived units partway down, *so you wouldn't have to include the instruction that Freie Universität Berlin posted at the top to indicate they were breaking from convention*, presumably for the sake of typographic brevity.
> 
> I'll fix that for you here:
> 
> ...



<dies laughing>


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## B-Cubed (Apr 12, 2011)

myCATpowerlifts said:


> What's your ego and where is it located?



That question is completely superfluous the the discussion at hand.


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## myCATpowerlifts (Apr 12, 2011)

B-Cubed said:


> That question is completely superfluous the the discussion at hand.



Deflection.
A commonly used female tactic to avoid acknowledgement of an
inferior argument.

If this is superfluous to the discussion, then why did you make a post
about it?


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## B-Cubed (Apr 12, 2011)

myCATpowerlifts said:


> Deflection.
> A commonly used female tactic to avoid acknowledgement of an
> inferior argument.
> 
> ...



It's not deflection.  When you posted your question you conveniently left off the part that asked why the OP why he thought I was "pushing it." The OP made it personal when he posted that.  My response about his "ego" was merely a side note on the way people make it personal when they can't admit that they are wrong.  And yes, indeed, my comment was superfluous to the discussion.  As are all the sexist remarks.


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## patricio (Apr 12, 2011)

Oh, my! I've just realized that this is the first time since I joined the forum that I disagree with Built! Tell me, Built, will I be punished  this? I was thinking black tight leather clothes and a whip ;-p


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## NeilPearson (Apr 12, 2011)

B-Cubed said:


> Why is that "pushing it?"  It makes it sound like your ego is very attached to being right. Further, your need to rely on irrelevant sexist remarks about women not being able to do math to bolster your position is further evidence that your argument is spurious.
> 
> On the other hand, I don't need to call you names or resort to insults. My ego is completely unattached to whether or not you can recognize a correct mathematical argument or not.  Mathematics is totally impartial.
> 
> It doesn't matter what it "looks like." Operations proceed from left to right with multiplication and division having the same level of precedence.  This means that a is divided by the 2 first and the result of that operation is multiplied by b, hence a/2b=(a/2)xb.



I'll forgive you since you are new but this website is all about irrelevant sexist remarks... It's what makes it fun.

so if it looks like this:

a
____
  2b

does it matter now?  My point is how it is written. With a/2b it looks like it is under the line just as much as my above example.


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## NeilPearson (Apr 12, 2011)

Built said:


> Oh - I see what you did here - you began the list of SI Derived units partway down, *so you wouldn't have to include the instruction that Freie Universität Berlin posted at the top to indicate they were breaking from convention*, presumably for the sake of typographic brevity.
> 
> I'll fix that for you here:
> 
> ...



Actually I didn't start it half way down to not post that part... I was in a hurry (going to work) and didn't actually read that part.

Yes they did mention "(Please note: all units to the right of the slash are actually in the denominator!)" because they are explaining the convention they are using... which seems a pretty common one because I see it on lots of other sites that don't explain.

They never said they are breaking from convention.  They said "(Please note: all units to the right of the slash are actually in the denominator!)"... this is because when written on a single line like that, it is kind of ambiguous and could be taken either way.


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## NeilPearson (Apr 12, 2011)

patricio said:


> "The general consensus among math people is that "multiplication by juxtaposition" (that is, multiplying by just putting things next to each other, rather than using the "??" sign) indicates that the juxtaposed values must be multiplied together before processing other operations"
> The Order of Operations: More Examples
> Even though math is an exact science, there are habits or uses in every science, where people tend to do the same thing when presented to the same problem, just to avoid interpretation.
> Just my two centd


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## NeilPearson (Apr 12, 2011)

Built said:


> Oh - I see what you did here - you began the list of SI Derived units partway down, *so you wouldn't have to include the instruction that Freie Universität Berlin posted at the top to indicate they were breaking from convention*, presumably for the sake of typographic brevity.
> 
> I'll fix that for you here:
> 
> ...



This doesn't help your argument.  They aren't saying they are breaking from convention.  They are simply explaining because the notation isn't as cut and dry as you say (or they wouldn't have to explain it)

And it does nothing to explain the other two links that use the same convention and don't feel a need to explain (because it is obvious)


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## NeilPearson (Apr 12, 2011)

Evaluating Algebraic Expressions Order of Operations/P.E.M.D.A.S.

This page takes you through this equation

(4-2)^3 + (3+2)^2 / 5(8-7)

Here are the steps

2^3 + (3+2)^2 / 5(8-7)

2^3 + 5^2 / 5(8-7)

2^3 + 5^2 / 5(1)

8 + 5^2 / 5(1)

8 + 25 / 5(1)

.... and for the most interesting step... drum roll....

8 + 25 / 5

Yes, that's right, they did the right multiplication first


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## NeilPearson (Apr 12, 2011)




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## NeilPearson (Apr 12, 2011)

It seems that text books and math authorities don't all agree on this either and that different conventions are in use.

This is the best answer I have been able to find:

"Mathematics is supposed to provide you with single, definitive answers. However, in this case, it does not. I really scoured the internet and countless textbooks for the proper answer and have made inquiries with few people I know whom I venerate as some of the greatest minds that I have had the luxury of meeting and the answer isn't as definitive as you would hope. Sadly, the real answer is that both sides are correct to a point. (…and it pains me to even remotely admit that anything outside of 288 could be the answer).

Position 1: The Order of Operations: This stance states that since the standard order of operations puts multiplication and division on the same rank, the equation can be read as (48÷2)*(9+3). This reigns with truth as 48÷2(9+3) is the same as 48÷2*(9+3). Using the standardized left-to-right notation, the answer can be nothing outside of 288. This left-to-right concept is indicative of “PEMDAS” that we all learned in grade school.

Position 2: The Distributive Property: This stance states that multiplication through juxtaposition, being a commonplace concept, naturally makes a parenthetical implication around grouped numbers. Thus, the equation appears as 48÷[2(9+3)]. This technique is correct as well. However, this makes the answer 2.

If you are bored enough to read [reference 1], you’ll see that the writer has noted multiplication by juxtaposition as being used in algebraic nomenclature dating as far back as the fifteenth century. That being said, the standard left-to-right order of operations predates even that. The real problem is that both techniques are taught in our school systems, depending on the chosen literature. Both forms can be found dating far enough back that there’s a solid argument for either chosen notation. Sadly, there is no current ‘authority’ to standardize which is appropriate. As Doctor Peterson mentions in [reference 2] “When algebraic notation was first being developed, it was common for each writer to begin by explaining his own notation.” That seems to still be true as students are still being taught the distributive property and multiplication by juxtaposition as well as the standardized left-to-right order of operations. The correct answer breaks down to who is asking the question.

As much as you’d like it to be a single definitive answer, alas, it is not. In my opinion, that needs to change. Someone should standardize it. But the real answer here, to end all further questions on this topic, is the ambiguity of the formula makes it faulty to begin with. No self respecting mathematician would have used this notation. Formula ambiguity can destroy the outcome. This should have been written as 48 / (2 * (9+3)) or (48 / 2)*(9+3), thus guaranteeing the desired result. 

To summarize, as much as one would like to claim one answer or the other, the sad reality is; being as there is no current standardization in this case, the answer is relative to the inquirer. In the future, if an “ab/cd” –type equation is proposed, you’re better off inquiring as to the proposer’s notation preference.
Source(s):
[Reference 1]: Earliest Uses of Symbols of Operation
[Reference 2]: http://mathforum.org/library/drmath/view/57021.html "


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## rockybaudoin05 (Apr 12, 2011)

2 all day every day son


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## NeilPearson (Apr 12, 2011)

B-Cubed said:


> It's not deflection.  When you posted your question you conveniently left off the part that asked why the OP why he thought I was "pushing it." The OP made it personal when he posted that.  My response about his "ego" was merely a side note on the way people make it personal when they can't admit that they are wrong.  And yes, indeed, my comment was superfluous to the discussion.  As are all the sexist remarks.



Sexist remarks are never superfluous to the discussion on this site... either are random "You're Gay" pictures


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## HialeahChico305 (Apr 12, 2011)




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## Built (Apr 13, 2011)

NeilPearson said:


> Actually I didn't start it half way down to not post that part... I was in a hurry (going to work) and didn't actually read that part.
> 
> Yes they did mention "(Please note: all units to the right of the slash are actually in the denominator!)" because they are explaining the convention they are using... which seems a pretty common one because I see it on lots of other sites that don't explain.
> 
> They never said they are breaking from convention.  They said "(Please note: all units to the right of the slash are actually in the denominator!)"... this is because when written on a single line like that, it is kind of ambiguous and could be taken either way.



This was a German site, and considering so much of the notation mathematicians use comes through Leibniz (THANK GOD - if you've seen Newton's notation, you'd be as grateful as I am!), I'm sure they were establishing that these units of measure are to be read as if the slash indicates a fraction rather than a simple division, as would otherwise be the convention. 

Germans are famous for engineering and for calculus (ask a German who invented calculus and the answer is "Leibniz"; ask a Scot and it's "Newton"), and as a culture, are rule-abiding. The explanation offered on a German educational site is in keeping with this; they were breaking from convention because they were listing units of measure, not calculation formulae; the notation (on that, and on the other pages you linked) is shorthand, and within this context, and with the explanation in place, it is clear. 

Personally, I blame calculators for a lot of this mess. Not for the usual reasons - I don't think they are evil or that they make people lazy; in the real world if you don't use computers for your calculations, nobody would trust your results. No, my reason for blaming them comes from what is written on the buttons, and by how their algorithms are sometimes designed. 

We've already seen instances of where calculation algorithms don't jive, but consider trigonometry for a moment. Inverse functions undo each other, right? These are not always simply reciprocal function, and yet, this is exactly the way most calculators indicate them. For example, the inverse of tan(x) is arctan(x), yet calculators indicate this as tan^-1(x). I've taught trig to grade 12 students who did not even know the word "arctan" - they just call it the inverse tan; I've had a number of these students not realize that inverse tan and 1/(tan(x)) are not the same thing. Given the now-standard notation for which we can thank calculator buttons, this is unsurprising. 

Other than some of the calculators I have tried, I have never before seen the juxtaposition rule being interpreted in this way - and I have studied both number theory, and math history.

When manipulating symbols, it is standard notation to leave off the multiplication operator - thus "a" times "b" becomes simply "ab". We cannot do this with numbers unless they're beside a bracket: 2 x 5 written this way would become 25, which is clearly wrong, although 2(5+6) is plainly equal to 2??(5+6); thus the operator is omitted. 

This statement: b(c+d) would virtually NEVER be written as b??(c+d), because there is no question that they are equivalent in every way, whether or not as part of a larger calculation. 

That being said, "eschew obfuscation" is a motto of mine, and to be perfectly fair, were I to write a question such as a÷b(c+d) , I would likely arrange it as either a(c+d)÷b, or, if I meant for the entire right hand side to act as a divisor, as a÷(b(c+d)) so as not to trick the reader.

When I design instructional math questions (I still tutor the occasional student), I try hard to keep this in mind. I want them to demonstrate fluency in mathematics, not the ability to second-guess the notation I've offered.


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## myCATpowerlifts (Apr 13, 2011)

I'm a Scot and I take offense to this post.


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## Built (Apr 13, 2011)

myCATpowerlifts said:


> I'm a Scot and I take offense to this post.



From one Scot to another, then.

Heh - a battle between Scots. Wasn't that how copper wire was invented - two Scots, fighting over a penny?


----------



## myCATpowerlifts (Apr 13, 2011)

Built said:


> From one Scot to another, then.
> 
> Heh - a battle between Scots. Wasn't that how copper wire was invented - two Scots, fighting over a penny?



My grandfather Murry Neal, supposedly holds partial rights to the copper wire patent.
He worked for Nasa in the 60's and 70's.

Too bad he's became a religious nutter, and doesn't give me any dough.


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## NeilPearson (Apr 13, 2011)

Built said:


> Other than some of the calculators I have tried, I have never before seen the juxtaposition rule being interpreted in this way - and I have studied both number theory, and math history.



You've seen examples of it now


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## myCATpowerlifts (Apr 13, 2011)

IN all seriousness though, I'm considering switching my major to Math.
Thoughts? I want to go to grad school when i finish my undergrad.
I wouldn't mind a phD either.

I'm 4 years deep, having classes in Computer Science, business, and Psychology.
But I don't want to pursue any of those degree plans anymore.
I have a decent chunk of school debt. but honestly, I couldn't give a fuck.
The system is fucked anyway. Resistance is futile.

Might as well just keep using the free aid.


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## maniclion (Apr 13, 2011)

NeilPearson said:


> Evaluating Algebraic Expressions Order of Operations/P.E.M.D.A.S.
> 
> This page takes you through this equation
> 
> ...



As far as my schooling goes ^ usually mean exponent so ....huh? Wow dude....


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## LightBearer (Apr 13, 2011)

48÷2(9+3) = ? | Know Your Meme

AHA!


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## myCATpowerlifts (Apr 13, 2011)

maniclion said:


> As far as my schooling goes ^ usually mean exponent so ....huh? Wow dude....



why're you confused?? The exponents were all done correctly.
First he Did Parentheses. then he did exponents. PEMDAS


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## maniclion (Apr 13, 2011)

myCATpowerlifts said:


> why're you confused?? The exponents were all done correctly.
> First he Did Parentheses. then he did exponents. PEMDAS


Because he is saying they did the multiplication first which I was like he can't be thinking he has some victory because the multiplication is by 1 so he must be confusing the exponents for multiplication....


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## NeilPearson (Apr 13, 2011)

maniclion said:


> Because he is saying they did the multiplication first which I was like he can't be thinking he has some victory because the multiplication is by 1 so he must be confusing the exponents for multiplication....



It doesn't matter if the multiplication is by one or not.  True, it doesn't affect the outcome of the equation but the fact is they did the 5(1) multiplication first.  Had it been a different number than 1, it would have made a difference.


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## NeilPearson (Apr 13, 2011)

maniclion said:


> As far as my schooling goes ^ usually mean exponent so ....huh? Wow dude....



Yes, that means exponent... and there is no debate that that part was done correctly.  

The debate is at this point:

Does 8 + 25 / 5(1) simplify to

8 + 5(1)   

or

8 + 25/5


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## jagbender (Apr 13, 2011)

Someone unplug the Eveready Bunny PLEASE 
It keeps going and going and   AWW crap you get the idea


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## Marat (Apr 13, 2011)

neilpearson said:


> does 8 + 25 / 5(1) simplify to
> 
> 8 + 5(1)
> 
> ...



8 + 5(1)   ?


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## independent (Apr 13, 2011)

My 11 year old got it correct.


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## ihateschoolmt (Apr 13, 2011)

....which answer are you saying is right lol


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## myCATpowerlifts (Apr 14, 2011)




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## jagbender (Apr 14, 2011)

Teacher arrested at John F. Kennedy Airport

A teacher was arrested today at John F. Kennedy International Airport as he attempted to board a flight while in possession of a ruler, a protractor, a compass, a slide-rule, and a calculator.

At a morning press conference, the Attorney General said he believes the man is a member of the notorious Al-Gebra movement. He did not identify the man, who has been charged by the FBI with carrying weapons of math instruction.

'"Al-Gebra is a problem for us," the Attorney General said. "They derive solutions by means and extremes, and sometimes go off on tangents in search of absolute values." They use secret code names like 'X' and 'Y' and refer to themselves as "unknowns", but we have determined that they belong to a common denominator of the axis of medieval with coordinates in every country.

As the Greek philanderer Isosceles used to say, 'There are 3 sides to every triangle'.

When asked to comment on the arrest, President Obama said, "If God had wanted us to have better weapons of math instruction, he would have given us more fingers and toes." White House aides told reporters they could not recall a more intelligent or profound statement by the President. It is believed that the Nobel Prize for Physics will follow.


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## myCATpowerlifts (Apr 14, 2011)

jagbender said:


> Teacher arrested at John F. Kennedy Airport
> 
> A teacher was arrested today at John F. Kennedy International Airport as he attempted to board a flight while in possession of a ruler, a protractor, a compass, a slide-rule, and a calculator.
> 
> ...


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## lifterjaydawg (Apr 14, 2011)

lol, very funny


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## MyK (Apr 15, 2011)

NeilPearson said:


> Yes, that means exponent... and there is no debate that that part was done correctly.
> 
> The debate is at this point:
> 
> ...


 
either


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## B-Cubed (Apr 19, 2011)

myCATpowerlifts said:


> IN all seriousness though, I'm considering switching my major to Math.
> Thoughts? I want to go to grad school when i finish my undergrad.
> I wouldn't mind a phD either.
> 
> ...



If you plan to go to graduate school to get a degree in mathematics, plan on having no life outside of graduate school for at least 4, but more likely 5-6 years.  Be prepared to eat, live and breath mathematics.  Be prepared for your girlfriend to complain that all you do is math, that she never sees you, and that you've become boring because it's all you ever talk about any more.  You'll wake up in the morning thinking about math, fall asleep in the evening think about math, and then you will dream math and have to wake up and do it all over again. If you want a PhD in math, you better really like it, because it is not a degree for the feint of heart.  Most of the math PhD's I know (just a few) would say they got their degrees out of an irrational stubbornness and refusal to give up.


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## tommyel56 (Apr 20, 2011)

NICE POST (Just trying to get my post count to 50 so I can PM... SORRY!)


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## LAM (Apr 22, 2011)

I had my gf submit this question to here math professor at UNLV, he said the answer is 2


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## myCATpowerlifts (Apr 22, 2011)

LAM said:


> I had my gf submit this question to here math professor at UNLV, he said the answer is 2


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## hoyle21 (Apr 22, 2011)

LAM said:


> I had my gf submit this question to here math professor at UNLV, he said the answer is 2




He/she is wrong, it is 288.   I still maintain that it is horribly written and nobody in the real world would write it that way.


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## LAM (Apr 22, 2011)

hoyle21 said:


> He/she is wrong



I highly doubt that...


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## ihateschoolmt (Apr 22, 2011)

Obviously NO ONE is about to admit they are wrong, someone with a doctor in math said it's 288 and apparently now a math teacher at UNLV says it's 2. Even calculators are giving both answers. I'm sure one is technically right, but no one is ever going to change the side they picked from the start.


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## Built (Apr 22, 2011)

hoyle21 said:


> He/she is wrong, it is 288.   I still maintain that it is horribly written and nobody in the real world would write it that way.


No instructor of any repute would write a question that way, to be sure. 



LAM said:


> I highly doubt that...


On what basis? That a math teacher in Las Vegas said so to your girlfriend? You've heard directly from a published, tenure-track professor of Mathematics that the converse is true. I mean Vegas? Mathematicians regard gambling as a tax for being bad at math!

The only issue is the order of operations with regard to a number written beside an expression inside parenthesis. 

The question" Is 48÷2(9+3) = 288 or 2?" really boils down to this: 
"is 48/2(12) the same as 48/2x12 or even 48/2x(12)?"

Some see them as interchangeable, and some do not.

Among posters who see them as interchangeable, there are at least three individuals who have worked, or who currently work, in in the field of mathematics. 



ihateschoolmt said:


> Obviously NO ONE is about to admit they are wrong, someone with a doctor in math said it's 288 and apparently now a math teacher at UNLV says it's 2. Even calculators are giving both answers. I'm sure one is technically right, but *no one is ever going to change the side they picked from the start*.


Indeed.


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## DOMS (Apr 22, 2011)

I thought is was 2, but Google thinks otherwise.


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## DOMS (Apr 22, 2011)

Then I looked up Order of Operations (emphasis mine).


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*First* do        all operations that lie *inside parentheses*.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Next, do        any work with exponents or radicals.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Working from        *left to right*, do all multiplication and division.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Finally,        working from left to right, do all addition and subtraction.[/SIZE][/FONT]
 Start: 48÷2(9+3)
Next: 48÷2(12)
Next: 24(12)
Final: 288

I think the key point is when the operators are at the same level, as they are with multiplication and division, you work from left to right.


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## Built (Apr 22, 2011)

Gotta love logic and consistent rules.


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## DOMS (Apr 22, 2011)

ihateschoolmt said:


> Obviously NO ONE is about to admit they are wrong, someone with a doctor in math said it's 288 and apparently now a math teacher at UNLV says it's 2. Even calculators are giving both answers. I'm sure one is technically right, but no one is ever going to change the side they picked from the start.



I beg to differ.


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## DOMS (Apr 22, 2011)

Built said:


> Gotta love logic and consistent rules.



No doubt.

I find it funny that KelJu said:



> But you have to appreciate the beauty of math. Had this been an abstract  concept, we would have a 20 page thread on our hands with flames and  death threats between the divided groups of twoions and  twohundredandeightyeightions.



Which is pretty much what happened.


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## ihateschoolmt (Apr 22, 2011)

DOMS said:


> I beg to differ.


About people switching sides? DAMN fine, most people won't change their mind. Happy?


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## DOMS (Apr 22, 2011)

ihateschoolmt said:


> About people switching sides? DAMN fine, most people won't change their mind. Happy?



Define "most"?


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## ihateschoolmt (Apr 22, 2011)

most  (m
	

	
	
		
		

		
			





st)_adj._ Superlative of many, much. 
*1. **a. * Greatest in number: won the most votes.
*b. * Greatest in amount, extent, or degree: has the most compassion.
*2. * In the greatest number of instances: Most fish have fins.


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## Built (Apr 22, 2011)

DOMS said:


> Define "most"?


Those lesser than yourself.


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## DOMS (Apr 22, 2011)

ihateschoolmt said:


> most  (m
> 
> 
> 
> ...



Dude, I was joking.


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## DOMS (Apr 22, 2011)

Built said:


> Those lesser than yourself.



Roger that.


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## ihateschoolmt (Apr 22, 2011)

DOMS said:


> Dude, I was joking.


I know I was just fuckin with ya.


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## hoyle21 (Apr 23, 2011)

Somebody needs to tally the votes just to make sure half of the people here got it wrong.


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## Built (Apr 23, 2011)

I considered doing that, but once again, laziness prevailed.


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## ihateschoolmt (Apr 23, 2011)

48÷2(9+3) = ???? - Page 41 - Grasscity.com Forums

Grasscity has a poll with over 200 votes, it was exactly 50/50. It's amazing that someone thought of a math concept that is so hard to prove based on what everyone has been taught.


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## Jodi (Apr 29, 2011)

Not reading this whole thread however, wanted to throw my answer in.  

288

48÷2(9+3)

PEMDAS, BODMAS whichever you use - they both mean the same thing.

Parenthesis first so 9+3 = 12
Then Multiplication or Division next but seeing there are both in this equation then order of operations are left to right:  48÷2=24
Then the multiplication of:  24x12= 288


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## myCATpowerlifts (Apr 29, 2011)




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## bentoverrows (May 3, 2011)

I think 2.
Order of Operations - BODMAS


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## otis332 (May 6, 2011)

48÷2(9+3)    Googled=  288!


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## myCATpowerlifts (May 6, 2011)

The answer is 2.

Anyone saying contrary needs to visit elementary school.


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## poleguy54 (May 6, 2011)

easy answer is 2


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## DOMS (May 6, 2011)

poleguy54 said:


> easy answer is 2


*Fail

*


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## ihateschoolmt (May 6, 2011)

You guys still arguing about this? You really think at this point 1 more person posting "it's 2 (or 288) omg u guyz r so dumb" is going to end it?


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## Iroc86er (Jun 7, 2011)

Haha I'll do it hate.

Not sure if anyone came to a conclusion, but the answer should be 2.

48/2(9+3) 

If you treat 9 and 3 as variables.  9=a, 3=b
48/2(a+b) = 48/(2a+2b)
48/(18+6)
48/24= 2

Wouldn't do it any other way.


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## danzik17 (Jun 7, 2011)

Thanks.  Thanks for bringing this retarded thread back after it finally died.


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## Ichigo (Jun 7, 2011)

It = 2


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## Iroc86er (Jun 8, 2011)

No problem fellas lol.


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## Kathybird (Jun 8, 2011)

So, what's the answer?  This is why I lost my damn scholarship.  I can correct every misspelled and grammatically incorrect post, but I can't balance my checkbook.


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## Kubush (Jun 8, 2011)

*288!*



Iroc86er said:


> Haha I'll do it hate.
> 
> Not sure if anyone came to a conclusion, but the answer should be 2.
> 
> ...




You can't distribute 2 by itself. The number as it is written can be seen as a fraction (48/2) which is then distributed. So it would be: (48/2)*a +(48/2)*b

If you plug in the numbers you get 288.


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## Kubush (Jun 8, 2011)

I was confused a bit at first too because I assumed that the "2(9+3)" was the denominator of the equation. So in my mind it looked like this: 
  48        
   2(9+3)

which equals 2.

But on re-examination I realized that as it is written it should look like this instead:
 48 * (9+3) = 288
    2


This is ultimately where the confusion lies.

Another example would be: 1/2(10) which is the same as 0.5(10)
The analogous mistake would be to do this: 1/(2(10)) = 1/20


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## whirledps (Jun 9, 2011)

The order of operations and left to right makes me say 288


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## 2003 V-ROD (Jun 9, 2011)

hoyle21 said:


> Somebody needs to tally the votes just to make sure half of the people here got it wrong.


 
I would but I'M TOO lazy and I hate Algebra.


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## SamuelTaylor (Jun 12, 2011)

2


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## Kubush (Jun 13, 2011)

No, it is 288.


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