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Solve this simple math problem: 48/2(9+3)

288 or 2 ?

  • 288

    Votes: 154 48.4%

  • 2

    Votes: 164 51.6%
  • Total voters
    318
Status
Not open for further replies.
Answer is 2

People seam to be forgetting distributive properties when dealing with this equation. Consider the following:
48/(9x+3x) = 48/x(9+3) The X is part of the Parenthesis.

48/(18+6), with this everyone would get 2

now, pull a 2 out and you have:

48/2(9+3) = 2

Seams pretty simple if you understand distributive properties.
 
oakscastle said:
People seam to be forgetting distributive properties when dealing with this equation. Consider the following:
48/(9x+3x) = 48/x(9+3) The X is part of the Parenthesis.

48/(18+6), with this everyone would get 2

now, pull a 2 out and you have:

48/2(9+3) = 2

Seams pretty simple if you understand distributive properties.
Click to expand...

You got your first equation wrong. Quite an achievement, I dare say!
 
I've seen problems like this before. :)

The issue is always that some people read PEMDAS incorrectly, assuming that multiplication is performed prior to division, as it appears first in the acronym.

In fact, (multiplication and division) along with (addition and subtraction) have the same level of precedence, and are simply performed left-to-right.

48 / 2 (9 + 3)
parentheses first
48 / 2 x 12
left-to-right, NOT 'multiplication then division'
24 x 12

= 288

:)

(There is of course, the obvious confusion as to whether the divisor acts like a 'bar', separating the 'top and bottom' sections of the equation. I think it's safest to assume that it does not. Don't lose any sleep, that aspect of the problem is totally up to an individual's interpretation.)
 
Last edited:
To add to dominickator post.

There is one fundamental issue that the 288 folks do not understand, or do not know, or whatever.

2(9+3) is NOT the same as 2*(9+3)

As standalone expressions, they will yield the same result. However, when used as part of another expression they are NOT the same. The lack of the operand is the key, this denotes that the 2 is part of the parenthesis and must be resolved before moving to the 'E', we are using PEMDAS.

[EDIT:]
I just realized the 288 folks are changing the equation, which is why you get 288. Follow the rules!

48/2(9+3) = 48/2(12) [Note, you still have parenthesis], so 48/2(12) = 48/24 = 2

NOT, 48/2*12 This is NOT the equation as written, so follow your own rules and you will get 2.
 
Last edited:
oakscastle said:
[EDIT:]
I just realized the 288 folks are changing the equation, which is why you get 288. Follow the rules!

48/2(9+3) = 48/2(12) [Note, you still have parenthesis], so 48/2(12) = 48/24 = 2

NOT, 48/2*12 This is NOT the equation as written, so follow your own rules and you will get 2.
Click to expand...

If you do the equation as you wrote and follow the rules, you have to divide 48 by 2 first then multiply by 12. The rules of PEMDAS clearly state that when you do multiplication and division, you go left to right; you don't do multiplication first. Same thing when you get down to Addition and Subtraction. Its left to right not Adding first, subtracting second.
 
Mac'nCheese said:
If you do the equation as you wrote and follow the rules, you have to divide 48 by 2 first then multiply by 12. The rules of PEMDAS clearly state that when you do multiplication and division, you go left to right; you don't do multiplication first. Same thing when you get down to Addition and Subtraction. Its left to right not Adding first, subtracting second.
Click to expand...

I agree with PEMDAS and L-R, but 2(12) is not the same as 2*12. You need to finish P before you move on. Therefore, 2(12) must still be resolved to 24.
 
oakscastle said:
I agree with PEMDAS and L-R, but 2(12) is not the same as 2*12. You need to finish P before you move on. Therefore, 2(12) must still be resolved to 24.
Click to expand...

You did finish P first. Its is down to one number and no more work needs to be done with it. When a number is next to another number that is in (), multiplication is just as implied as if you had a * or X in between the two.
 
Mac'nCheese said:
You did finish P first. Its is down to one number and no more work needs to be done with it. When a number is next to another number that is in (), multiplication is just as implied as if you had a * or X in between the two.
Click to expand...

Well, I see where our differances are and I must respectfully disagree. If a number is next to the (), then you must use distributive Properties to fully resolve the () - you cant just treat it as multiplication. All my math from grade school to Calc taught this, which is why I must disagree. :)
 
oakscastle said:
Well, I see where our differances are and I must respectfully disagree. If a number is next to the (), then you must use distributive Properties to fully resolve the () - you cant just treat it as multiplication. All my math from grade school to Calc taught this, which is why I must disagree. :)
Click to expand...

Ok fair enough to agree to disagree. Good day to you, sir. :)
 
oakscastle said:
Well, I see where our differances are and I must respectfully disagree. If a number is next to the (), then you must use distributive Properties to fully resolve the () - you cant just treat it as multiplication. All my math from grade school to Calc taught this, which is why I must disagree. :)
Click to expand...

Thanks so much for re-opening this dead thread with your bogus logic.:rolleyes:
 
oakscastle said:
Well, I see where our differances are and I must respectfully disagree. If a number is next to the (), then you must use distributive Properties to fully resolve the () - you cant just treat it as multiplication. All my math from grade school to Calc taught this, which is why I must disagree. :)
Click to expand...

You know, I was going to post something more involved about how depressing it is you made it through that much math and do not realize this equation is equal to 288, though misleading, but I'm just going to tell you to read the thread instead, since plenty of people have already made the logical arguments which unequivocally support that expression having a value of 288.

The only time it doesn't is if you make assumptions. And you know what they say about assumptions... ;)
 
First off, I'd like to thank Mac'NCheese for a civil disagreement. As for the rest of you who can't find anything better to do than to be sarcastic and degrading - shove it!!
ender land: I could say the same about you. From where I am standing, I can not understand how anyone can miss, or not understand simple distributive properties - which is depressing. As for this thread "proving" 288, there are plenty of posts proving it's 2.
 
So 48/2(9+3)

becomes

48 divided by two times twelve


(since we all agree - hopefully :confused: - this reduces to at least 48/2(12)


Do order of operations on the sentence above and you'll find your answer, and it's not 2 ;)

Unless of course you for some reason read the equation to be - 48 / 2(9+3) - which is an assumption outside what is actually written.
 
It's not that we disagree on the order of operations, we disagree on the meaning of 2(12). You state this = 2*12, I disagree and believe you still have to use distributive properties to completely resolve the (). It has nothing to do with performing the M and D calculations L-R, I do that after I have resolved the ().
 
Has anyone made the point that if written out instead of typed, the problem would logically look like this:


48
_____

2(9+3)


??

At least it would have been when I was in school, before computers took over the world. It just doesn't seem like it would be

48/2
_____

(9+3)


But that would give you the same answer.

Turning it into 24*12 just seems wrong intuitively. To me, getting there would require it to be written as (48/2)*(9+3)

I dunno. Just a layman's perspective.
 
Gregg2 said:
Has anyone made the point that if written out instead of typed, the problem would logically look like this:


48
_____

2(9+3)


??

At least it would have been when I was in school, before computers took over the world. It just doesn't seem like it would be

48/2
_____

(9+3)


But that would give you the same answer.

Turning it into 24*12 just seems wrong intuitively. To me, getting there would require it to be written as (48/2)*(9+3)

I dunno. Just a layman's perspective.
Click to expand...

Yes, in the real world, this might be written differently to make it clearer, but the point of the exercise is that you can write a problem on one like that and even though it looks ambiguous, with order of operations, it's not ambiguous at all. Following OOO correctly, the answer is 288.
 
just broke the tie with a 288 vote

This thread should not die.

Amazing that it was tied before i voted. Had no idea it was. After reading though all the pages, still not clear why so many get to 2 as the answer, but it is fun reading though all the explanations.
 
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