Saw this in another forum and just had to ask what people here think:

48÷2(9+3) = ?

What is the answer, 288 or 2.

Apparently it originates from here:
http://forum.bodybuilding.com/showthread.php?t=133389973

 

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

Multiplication and division are left associative binary operators equivalent in operator precedence. Therefore, you read from left to right, applying the division first, then the multiplication.

Stylistically, when writing mathematical expressions that require a knowledge of operator precedence, it's good practice to use parentheses to dispel ambiguity.

 

I can't say I know anything about math(I'm an engineer heh) but I think multiplying is higher order then dividing, so it comes out 2. Even if you write it down in another format: 48 under it, the 2(9+3) then it also comes out to 2. But to be sure tomorrow morning I will ask my mother for you, she is a math teacher maybe she could lift the veil of mystery of this equation.

Edit: Ninja'd by Pers. But I will leave it here.

 

It's 288. Google wouldn't lie to us. :>

 

() are the highest in preference(order of operations).
Therefore, 9+3 = 12 * 2 = 24
24/12 = 2

Or if you distribute the 2...
2*9 + 2*3
18+6 = 24
48/24 = 2

But in CS you go left to right if all the operations are the same
(9+3) = 12
48 / 2 = 24
24*12 = 288

So depends on the type of math?

 

Who actually uses the division sign anyways? I don't even know where it is on my keyboard. 48/2(9+3) is a lot easier to see, and 24*12 = 288

 

To quote Math terms learned in school(don't know why I even remember it) but we were taught that it was BODMAS.

In order of precedence it was Brackets first, followed by the OF term(Again no clue why that was there but it was) followed by Division, Multiplication, Addition and then Subtraction. So yea working it out its 288 as Pers got it.

 

Interesting. This actually made me look up order of operations on Wikipedia, which states:

Going by this, then, the answer is 288. First, you do:

(9 + 3) = 12

and then go to division and subtraction, which goes from left to right, hence:

48 ÷ 2 [FONT=&quot]×[/FONT] 12 = 288

 

According to this page, ambiguously written fractions are to blame. Quoting:

Also:



Damn those conventions.

 

We always used the PEMDAS (parenthesis, exponents, multiplication, division, addition and subraction) abbreviation. I was lost for a second when someone said BODMAS. Didn't even know there were other abbreviations. >_>

 

What it comes down to is that some people think that multiplication by juxtaposition (when you have parentheses) has higher precedence than "normal" multiplication or division, which are normally of equal precedence.

Personally, I think it's better to treat multiplication by juxtaposition as normal multiplication (Google, Matlab, Wolfram|Alpha, python, etc. all agree), but I can understand the viewpoint that parentheses somehow add extra "stickiness" when multiplying.

In any case, the page Mustaine quoted is right. If there is a situation where this kind of miscommunication could arise, you should just use a less ambiguous form.

 

Why in fuck aren't you using an HP48 like any sensible person?

/old man

 

If I copy/paste it into my computer calculator, the answer is 2...

If I do it by hand (48÷2×12), how I was taught in school (PEMDAS), the answer is 288. What the balls. D:

 

My school taught me to distribute first, so without this thread I would fail at basic math. Thanks, DLP.

 

Distributing first is a good thing to do when there's variables and all the signs are multiplication.In cases where it's a complex fraction, it's more like they placed parentheses on both top and bottom (If that makes sense, I'm not very good at explaining it) . In any case, who uses division anymore? Sticking to multiplication and fractions/decimals.

48 * .5 * (12). Yay, 288 for the win.

 

That original thread is fucking hilarious. Not that half the people got it wrong (I would have too, but you made me double check by asking "2 or 228?"), but that a few of them were so stubbornly clinging to the wrong answer even after it was explained in twenty different ways.

Moral of the story:

 

Oh god, I read the original thread after you made that comment. Those people are freaking retarded (At least all the one that chose 2 and clung to it)

 

The differing calculator pictures likely stem from how some (or many, actually) simpler calculators totally disregard order of operations and compute the result of expressions in the order that they are given. The Calculator app that comes with Windows is an example of this - type in 2 + 5 * 3 and you get 21.

 

Brackets
Exponents
Division
Multiplication
Addition
subtraction

I've never heard of Bodmas? is Of some way of expressing Exponents. I've never heard it said like that.

Also Trust in the Pers

 

What's all this BODMAS malarky? BIDMAS master race.