# 48÷2(9+3)=?

#### Thomas Rembrandt

##### New member
why is 2 part of the bracket? It reads 48/2*(9+3) or x / y * z. If it read x / (y*z) you'd be right but thats not the case.

#### infohippie

##### New member
4li3n said:
Sikachu said:
So since there is no ambiguity here as he has not used the / which can be used for either a fraction line or division
In what way do you imagine fractions and division to be different?
He doesn't what he meant is that a fraction symbol can be seen as including everything after it below the fraction if you use it in a straight line of text instead of the classical way of stuff being clearly under and above.
Which is why you make liberal use of brackets if you're going to put everything on one line like that, otherwise you end up with ambiguity as seen here.

#### theklng

##### New member
TiefBlau said:
48 ÷ 2 * (9+3)
48 ÷ 2 * 12
24 * 12
288

Do not, do not, do not multiply the 2 and the 12. Multiplication/Division are of equal priority and go left to right.

You wouldn't say
48 - 2 + 12
48 - 14
34
Would you?
you're wrong. you release brackets first, so it would be 48/(18+6)

your other example is faulty logic, 48 - 2 + 12 = 48 + 10 = 58 (incidentally, (48 - 2) + 12 = 46 + 12 = 58).

#### imperialreign

##### New member
On second thought, I recant my original answer and am now substituting the following solution for all mathematical questions today:

42

#### TiefBlau

##### New member
There is no ambiguity.

Division and multiplication are interchangeable operators and in the notation that we all use, it goes left to right. There's no argument about this. There just isn't any. It's like arguing over whether or not "you're" and "your" are different words. They just aren't. That's just the language we use, and no amount of semantic bullshit is going to change that.

#### Durananrananrananran

##### New member

When I was about 5 or 6 years old, in primary school, in the playground, they was a small patch of tarmac about a metre square, at the side of the playground, around the corner from one of the buildings. All the kids from all the classes wanted to use that patch of ground as a 'spawn point' for various games of tag, hide and seek, and so on. Various groups would go there, start their game, and run around. And them come back to the hallowed patch. And another bunch of kids would be there. And an argument would start about who was there first: an argument that would go:

"We were here first."
"No we were here first, there was no one here when we got here, you idiots!"
"But we were here first, there was no one here when we got here either"

and it would go on like that until playtime ended.

That is what this thread is like.

#### luke10123

##### New member
BODMAS
brackets of divide multiply add subtract.
that's maths for a ten year old #### Pingieking

##### New member
4li3n said:
Except unlike the last time the symbol used kinda makes it clear that the 48 is divided by 2 and then you get the brackets...

And one last time: DIVISION AND MULTIPLICATION HAVE THE SAME PRIORITY IN MATH (as do addition and subtraction)... the equation should be read like this:

48*0.5*(9+3)

Now everyone tell me what that equals.

Unless you interpret x(z+y) as one element like some guy was that one time because the math level/type he was at used that symbol or something.
This. The original equation was just written in an annoying way. Rewrite it and it becomes clear.

48 / 2(9+3)=
48/2x12=
48/24=2

#### Lord Kloo

##### New member
I love BODMAS (I'm English we have to be different), probably one of my most favourite bits of maths..
I do believe the answer is 288 because you do:
Brackets = (9+3) = 12
Divide = 48/2 = 24
Multiply = 24 x 12 = 288
Yay for maths! - But this isn't exactly news to many peeps..

But its actually 2 because you do division and multiplication left to right..
But then thats a made up rule so I was right its 288.. stop trying to confuse me you evil people

#### theklng

##### New member
stomping all over everyone's faulty answers: http://en.wikipedia.org/wiki/Reverse_Polish_notation

gonna edit this post to put in faulty answerer(erer)s:

TiefBlau said:
There is no ambiguity.

Division and multiplication are interchangeable operators and in the notation that we all use, it goes left to right. There's no argument about this. There just isn't any. It's like arguing over whether or not "you're" and "your" are different words. They just aren't. That's just the language we use, and no amount of semantic bullshit is going to change that.

wrong. brackets > division. check the wiki link.

No the problem is when it is written as shown here there is no ambiguity like with the other equation. What you really have after brackets have done which you have stated is 48÷2*12=288. In this case you solve the equation from left to right as division comes before multiplication so 48/2 = 24. Then 24*12= 288.
wrong. brackets are STILL more important than division, especially when it comes to multiplying into brackets. check the wiki link.

#### The Unworthy Gentleman

##### New member
Nimcha said:
The Unworthy Gentleman said:
The 2 is a part of the brackets
Right, that's why it's outside of them. :O

Nice try, though.
Patronising, nice.

There are two sets of (9+3), not a half set of 48. Clearly this isn't going to help, so let me explain it another way. If the question wasn't 48 ÷ 2(9+3) and was instead 48 ÷ (9+3)^2 then we wouldn't have 16 because we have a squared set of brackets, not a squared overall answer. Similarly, we have two sets of (9+3) shown by having a 2 immediately outside of the brackets. Because it is immediately the equation cannot be rewritten as such:

48 ÷ 2 x (9+3)

but can be rewritten as this:

48 ÷ (9+3)2

It makes no difference to the way the equation works in the second form, but makes drastic changes to the way the equation works in the first one.

#### 4li3n

##### New member
Daniel Charlton said:
Division and multiplication are treated as equals so its just the closest one to the left is done first, the same goes with adding and subtracting
But mathematically there's nothing stopping you from doing it the other way around... and at times that might come up, and it's better to know the real way you do it instead of something you're taught out of convenience in 2nd grade.

#### ACman

##### New member
The 2 Seems to be part of the brackets so by order of operations BODMAS the answer is 2.

#### TiefBlau

##### New member
theklng said:
you're wrong. you release brackets first, so it would be 48/(18+6)
Oh dear. I don't think "release brackets" means what you think it means.

You operate on the brackets, meaning, whatever's inside the brackets is calculated first.

Hence, you first calculate (9+3) to be 12. Then it's multiplication/division, so you go left to right.

You don't distribute the 2. That's not even what the "brackets" operation is. Distribution is multiplication, which is interchangeable with division, so even if you wanted to do it that way, it'd be like this:

48 / 2 * (9+3)
24 * (9+3)
216 + 72
288
theklng said:
your other example is faulty logic, 48 - 2 + 12 = 48 + 10 = 58 (incidentally, (48 - 2) + 12 = 46 + 12 = 58).
You still don't get it...

#### Denamic

##### New member
Either is correct, depending on which system you use.
Ambiguous questions tends to get ambiguous answers.

#### Baron_Rouge

##### New member
They say BODMAS over here in Aus, or that's what I was taught anyway. Going by that, it's 288. Brackets first, (9+3)=12. So it becomes 48/2(12), or 48/2x12 to put it another way. Whether division comes first or you do division/multiplication at the same time, left to right, it works out the same. 48/2=24. 24*12=288.

#### 4li3n

##### New member
theklng said:
There are two sets of (9+3), not a half set of 48. Clearly this isn't going to help, so let me explain it another way. If the question wasn't 48 ÷ 2(9+3) and was instead 48 ÷ (9+3)^2 then we wouldn't have 16 because we have a squared set of brackets, not a squared overall answer. Similarly, we have two sets of (9+3) shown by having a 2 immediately outside of the brackets.
Actually dude as plenty of high schools do use 2(x+y) to mean 2*(x+y), and in the end the symbols themselves are just an agreed upon writing system neither interpretation is so much wrong then SH or an S with a ceddila being used for the same sound.

#### theklng

##### New member
TiefBlau said:
theklng said:
you're wrong. you release brackets first, so it would be 48/(18+6)
Oh dear. I don't think "release brackets" means what you think it means.

You operate on the brackets, meaning, whatever's inside the brackets is calculated first.

Hence, you first calculate (9+3) to be 12. Then it's multiplication/division, so you go left to right.

You don't distribute the 2. That's not even what the "brackets" operation is. Distribution is multiplication, which is interchangeable with division, so even if you wanted to do it that way, it'd be like this:

48 / 2 * (9+3)
24 * (9+3)
216 + 72
288
theklng said:
your other example is faulty logic, 48 - 2 + 12 = 48 + 10 = 58 (incidentally, (48 - 2) + 12 = 46 + 12 = 58).
You still don't get it...
you're talking to a programmer here, i've been doing math for longer than you've lived. i do these equations pretty much every day, why else would i link the goddamn system that makes everything uniform?