what say you...(math problem)

[srimes]

48/2(9+3)

48/2(9+3) = 48/2(12) = 48/2*12

This cannot be reasonably argued. The question is whether it was intended to be (48/2)12 or 48/(2*12).

As typed, the answer is 288.

1/2(2) = (1/2)2 = 2(1/2) = (2)1/2 = 1

 

[Crusher16]

so you agree the answer is 2, but since it's in texas and therefore bigger it MUST be 288

Exactly!

It is definitely 288.

Neither division nor multiplication take precedence over each other - they are the same operation. IE. 48/2 is the same thing as 48*(1/2). Similarly addition and subtraction are the same operation 4-7 is the same thing as 4+(-7).

Therefore 48/2(9+3) is the same as 48*(1/2)*(9+3).

Convention would state that if you wanted the multiplication operation of 2*(9+3) to precede the 48/2 you would need to override the commutative law by grouping the 2 and (9+3). Since they are not grouped, the commutative law holds and you can multiply in any order:

(1/2)*48*(9+3)
(1/2)*(9+3)*48
48*(9+3)*(1/2)
48*(1/2)*(9+3)
(9+3)*(1/2)*48
(9+3)*49*(9+3)

(9+3)48/2 & 48(9+3)/2would also yield the same result.

 

[WB9YZU]

I voted for 2

The reason being is that the formula as written can be interpreted either as 48/2 * (9+3) OR 48/(2*(9+3)) because the syntax is wrong.

 

[AIbandit]

I voted for 2

The reason being is that the formula as written can be interpreted either as 48/2 * (9+3) OR 48/(2*(9+3)) because the syntax is wrong.

Poorly written yes, wrong no.

Nothing in it would imply (2*(9+3))

 

[WB9YZU]

Poorly written yes, wrong no.

Nothing in it would imply (2*(9+3))

It is not poorly written, it was written like that on purpose. It's useless to argue over an obvious argumentative.

The reason why the question is posted in the first place is the same as a weird object left on a coffee table. It serves no other purpose than to start a conversation.

Your interpretation of the formula is based on your personal bias. Some read it one way, some read it another.

The poll shows that more people interpret it one way than another, though with more samples, I suspect it would become more like 50/50 after a while.

 

[CherBear]

I agree with the people who say the syntax is wrong. If you were writing this problem out on paper, no one in their right mind would write it that way. The answer depends on how you interpret the parenthesis. But the way this is written, the answer IMHO is 288.

 

[AIbandit]

It is not poorly written, it was written like that on purpose.

Just because it was written poorly intentionally doesn't mean it isn't poorly written.
If it was "wrong" it wouldn't work at all but it isn't wrong because using the order of operations it works.

"Parentheses, Exponents, Multiplication and Division, and Addition and Subtraction"

Sadly M and D couldn't be placed on top of each other in the acronym to eliminate confusion.


"When you have a bunch of operations of the same rank, you just operate from left to right."

 

[fyrfytr1717]

Just because it was written poorly intentionally doesn't mean it isn't poorly written.
If it was "wrong" it wouldn't work at all but it isn't wrong because using the order of operations it works.

"Parentheses, Exponents, Multiplication and Division, and Addition and Subtraction"

Sadly M and D couldn't be placed on top of each other in the acronym to eliminate confusion.


"When you have a bunch of operations of the same rank, you just operate from left to right."

Agreed! 288. Wasn't this like 6th or 7th grade math? No favoritism between *&/ or +&-, just read left to right like you would read any other sentence. Maybe I need to read the smart guy arguments in favor of 2 as the answer so I can understand where they're coming from.

And while Please Excuse Dear My Sally Aunt just doesn't sound right, it very well could have happened if some mathematician way back when wouldn't have had that bias toward listing operations that resulted in larger numbers first.

 

[CherBear]

Some one track down a good argument for the two answer. I just dont see how this would ever make sense.

Ill just let this link speak for itself:
http://www.wolframalpha.com/input/?i=48/2(9+3)

 

[urban yan]

Yeah, I just don't see how two's the answer either.

 

[AIbandit]

Some one track down a good argument for the two answer. I just dont see how this would ever make sense.

So far "You're Bias" is the best argument...

I just got that App haven't played with it yet. Was free on the amazon app store like 2 days ago

 

[outkast7222]

I just typed it into two different scientific calculators exactly as it is written and they both came up with 288....there for my vote goes for 288. I can completely understand the reasoning for the answer 2 also and there are good arguments for it. I really think its hard to know the real answer with out knowing what the formula was for. This was probably written for pure table-side talk and therefore will never have a correct answer.

That is also what I am up with before using the calculator. I remember being taught that multiplication and division were done left to right unless something was in parentheses.

That and you can ask my wife, I am ALWAYS right! LMAO

 

[AIbandit]

I can completely understand the reasoning for the answer 2 also and there are good arguments for it.

Where are they?

In the same post you write why it couldn't possibly be 2. There is no gray area it simply isn't 2 if you follow the rule. This is really a simple math problem it's sad to see this much debate.

I remember being taught that multiplication and division were done left to right unless something was in parentheses.

 

[bigalpha]

In PEMDAS multiplication and division have the same priority
so you do parenthesis then exponent then M/D then A/S
Parenthesis 9+3=12
M/D Left to right because we speak english (and that's the rule)
48/2 = 24 * 12=288

:thumbup:

 

[bluejeepkid]

parenthases (sp) first, always, PEMDAS, i think was the thing back in school

it's 2

stop doing your kids homework for them

lol if you had actually followed PEMDAS, you would know that the answer is 288. yes parenthesis first but then when it comes to multiplication and division, you do it from a left to right.. so 48/2x12=288


oops, guess i shoulda read the whole post first lol

 

[GrimmJeeper]

 

[akelts]

My graphing calculators says 2 so thats what I'm going with.

 

[CherBear]

I think everyone that has posted a logical argument has agreed with 288.

 

[srimes]

:thumbup:

 

[webbjeep]

The final Verdict ..... as a math guru ...... multiple degrees, etc. ..... you know expensive pieces of paper that state I know a lot of math.

Its 288 ....... as stated earlier PE(MD)(AS) as in mathematically Multiplication, and Division are "technically" the same as is Addition and Subtraction (subtraction is adding the opposite, ie a-b=a+(-b))

Therefore the parentheses are first, then Multiplication and Division as they appear left to right ......... then Addition and subtraction as they appear left to right.

Also I teach 8th grade algebra, we do this stuff all the time. Except all my examples involve Chuck Norris, kids love it, parents love it, administrators understand, but don't like it


On a side note, the question has the paren's around the 9+3 but seems purposefully left out of the (2(9+3)), thus its 288.