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48÷2(9+3)=

Pierre

Strata Poster
2 or 288?

Taken this from a football forum I visit and its turned into a proper lengthy discussion...

Even calculators are giving inconsistent answers.
 
Its 288

Basically it is 48 divided by 2 then multiply by the sum of 9 and 3 (which is 12). So 48 / 2 X 12 Simples =]
 
The problem is with how it's written. It is actually right either way.

Taking it to be (48÷2)(9+3), and using BODMAS:

(48÷2)(9+3)= [brackets]
24*12= [multiplication]
288

Taking it to be 48÷(2(9+3)), and using BODMAS:

48÷(2(12))= [brackets i]
48÷24= [brackets ii]
=2

So actually neither is wrong. ;) It's not really a fully specified question, I don't think. I think technically a mathematician (which I'm not) would say that the question has two solutions, and would be to be defined more clearly.
 
Pierre darling, I think the football lout in you is a bit more easily pleased than your coaster lout! :p
 
There's no brackets around the first part, it's 2.

Why would people make up brackets...?
 
^Again, you've got to do BODMAS...

48÷2(9+3) = 48÷2*12 = 24*12 = 288
 
^Technically the brackets don't instantly vanish after you sum 9 and 3, so you still have the 12 in them so it has to be multiplied out first...

But this is something that really comes down to how people were taught and learnt maths...
 
^Yeah, the brackets mean you times the 2 and 12 together before doing anything else...

That IS using BODMAS... You know... the B in BODMAS...?
 
^^No, the B in BODMAS (or BIDMAS as I use) actually only applies to the addition inside it. I'm with Hixee on this, it has two solutions.
 
Try writing it properly as 48/2(9+3), because is ÷ EVER actually used, then tell me how you'd solve it.

If it was written like an actual mathmatical problem would be, and not deliberatley misleading, then it does have one solution.
 
^OK.

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

Both options still work. Like I said before, an extra set of brackets are needed to clarify the problem.
 
^That's cause you're American...

Hixee said:
^OK.

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

Both options still work. Like I said before, an extra set of brackets are needed to clarify the problem.

No, because that's not what I meant by it being written as an actual mathmatical problem would be.

The way it's writtens suggests it would be written out as

48
----------
2(9+3)

Which would work out as 2.
 
^Yes, that would, but like I said, it depends where you put a set of brackets.

You want to put the extra brackets around the 2(9+3), so you get:

48
--------- = 2
2(9+3)

I'm saying you'd be just as entitled to put the brackets around the 48/2, to get:

48
--- x (9+3) = 288
2

I'll say it again, I don't think there is anything wrong with either solution. They're both right.
 
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