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# 48÷2(9+3) = ? watch

• View Poll Results: 48/2(9+3)
2
117
52.47%
288
106
47.53%

1. This isn't even year 7 stuff really. The answer is 2, have they never heard of BODMAS?
2. (Original post by kaosu_souzousha)
electronics say it is 288
Everyone can see that it is a poorly worded question, it's all about how the reader interprets it.

Try entering it as 48÷(2(9+3)) & then as (48÷2)(9+3), get the same answer?

I can see why people think its (48÷2)(9+3)=288, but to me, my intuition says its 48÷(2(9+3))=2. Since the 2 is associated with (9+3).

Otherwise the writer would have wrote like this

48(9+3)/2 or (9+3)48/2

but they didn't, so 2 it is.
3. (Original post by Lewk)
brackets always comes first, then youre just left with 48÷2x12, then you work from right to left, like computers/calculators (the more advanced ones anyway...) do. Just like 48÷12÷6 = 24, not 4/6

lol my calculator says 288 but its **** & can't even multiply negative numbers together so i'd go with yours ...
Is that really how calculators work? (I don't know, I read once how they work but forgot and all I remember was that it was a little more complex than that).

And my TI-84 says it is 288.
4. (Original post by kevin6767)
This isn't even year 7 stuff really. The answer is 2, have they never heard of BODMAS?
BODMAS does nothing here. The D and the M, as well as the A and the S, are interchangeable. Like everyone said, it's just poor notation, and the reason we have LaTeX.
5. Just use BIDMAS

Brackets first: 9+3 = 12

Then division: 48/2 = 24

Lastly, multiplication: 24x12 = 288

EDIT: I'm really surprised people can't grasp this.... I'm no mathematician, but seriously....
6. It's amazing how badly people misunderstand BODMAS. This is an example of where you can get the right answer but with a hitch in the understanding. Division doesn't take precedence over multiplication. Similarly, addition doesn't take precedence over subtraction. Each of those are just done from left to right.

48÷2(9+3)
or 48 ÷ 2 x (9+3)
Brackets first: 48 ÷ 2 x 12
Then work left to right. Division gives 24 x 12. Multiplication gives 288.

So. Brackets. Powers. Division and multiplication working left to right. Addition and subtraction from left to right.

For example. A really ambiguous looking calculation falls cleanly to the rules:

2 ^ 3 - 5 x (5 - 2) / 5 + 2

Brackets: 2 ^ 3 - 5 x 3 / 5 + 2
Powers: 8 - 5 x 3 / 5 + 2
Division and multiplication (left to right):
8 - 15 / 5 + 2 (multiplication done first)
8 - 3 + 2 (then the division).
Addition and subtraction (left to right):
5 + 2 (subtraction first)
7. http://www.wolframalpha.com/input/?i=48/2(12)

There is a clear distinction between your original question and dividing 48 by 2x for any x.
8. (Original post by Farmer Giles)
Everyone can see that it is a poorly worded question, it's all about how the reader interprets it.

Try entering it as 48÷(2(9+3)) & then as (48÷2)(9+3), get the same answer?

I can see why people think its (48÷2)(9+3)=288, but to me, my intuition says its 48÷(2(9+3))=2. Since the 2 is associated with (9+3).

Otherwise the writer would have wrote like this

48(9+3)/2 or (9+3)48/2

but they didn't, so 2 it is.
I agree with you. My first guess was 2 but all of my sources of artificial intelligence say it is 288 . Computer definitely interprets it as (48/2)*(9+3)
9. Crap question, fire whoever set it.
10. (Original post by Farmer Giles)

or

It may look ambiguous to some, but since the (9+3) is multiplied by the 2 it is safe to assume it goes with the denominator.

How about the (9+3) being multiplied by 48/2 ?

It really depends on how you personally interpret it.
11. I can't believe this is actually being debated, given we learnt the rules in, like, Year 7...

If the answer was 2, the LHS of the equation would have to be 48/(2(9+3))

In the equation given, because of the rules of order of operations, there are essentially implicit brackets: (48/2)(9+3) giving 288
12. (Original post by danny111)
How about the (9+3) being multiplied by 48/2 ?

It really depends on how you personally interpret it.
That would be the same as the second fraction wouldn't it.
13. There have been people on this completely contradicting themselves when using BODMAS (BIDMAS).
Working from left to right has no bearing on the correct outcome and is not how mathematics works, and in fact - working from right to left is probably used more commonly is this field.

Anyway... The order of operations question.
BRACKETS. ORDER/INDICES. DIVISION. MULTIPLICATION. ADDITION. SUBTRACTION.

1. 48/2(9+3)
- BRACKETS
= 48/2*12 'Any two separate numbers together automatically implies a multiplication. i.e. 2a = 2 * a

2. 48/2*12
- DIVISION
=24*12

3. 24*12
- MULTIPLICATION
=288

14. This is so ridiculously retarded. This retarded thread is 4 pages long. People actually think it's 2. Is this real life? You guys are so dumb is hurts. The way you are talking about basic maths which you should have been able to do when you were 7 is beyond belief. You're even having to type it into calculators. And you know what, talk about irony, this is on 'thestudentforum' - which is full of geeks; people who are so obsessed with education, they spend their free time to post about it.

16. The way I see it
48/ 2(9+3)
48/ (18 +2(3))
48/ (18+6)
=2
For example, it it were 48 / p(f+q) the first thing you would do is expand the brackets, getting 48/ pf +pq.
Same in this circumstance IMO.

If it were (48 ÷ 2) (9+3)

= 48(9+3) ÷ 2 (9+3)
= 432 + 144 ÷ 18 + 6
= 576 ÷ 24
= 24

If it were (48 ÷ 2) x (9 + 3)

= 24 x 12
= 288

But it is .. 48 ÷ 2(9+3) .. so according to BODMAS,

= 48 ÷ 2 x 9 + 2 x 3
= 48 ÷ 18 + 6
= 48 ÷ 24
= 2

.. Why are people multiplying the Value added to 2 .. which is (9+3) by 48 as well.. ?? (9+3) is only for 2 !!

18. I got two on my calculator using simple BIDMAS
Make the most of it then if you are doing a Maths degree or something.

Can't you write a report or something reharding this? Get known. Get job
19. (Original post by Eplkid)

If it were (48 ÷ 2) (9+3)

= 48(9+3) ÷ 2 (9+3)
= 432 + 144 ÷ 18 + 6
= 576 ÷ 24
= 24

If it were (48 ÷ 2) x (9 + 3)

= 24 x 12
= 288

But it is .. 48 ÷ 2(9+3) .. so according to BODMAS,

= 48 ÷ 2 x 9 + 2 x 3
= 48 ÷ 18 + 6
= 48 ÷ 24
= 2

.. Why are people multiplying the Value added to 2 .. which is (9+3) by 48 as well.. ?? (9+3) is only for 2 !!

Why the hell are you multiplying out the brackets...? This is not an 'expand' question. You complete the function that is WITHIN the brackets - following BODMAS (BIDMAS).

48/2(9+3)
Google it as written (Exact to the question).

20. (Original post by Agent Smirnoff)
I got two on my calculator using simple BIDMAS
Make the most of it then if you are doing a Maths degree or something.

Can't you write a report or something reharding this? Get known. Get job
Job .. Maybe not .. but I am more than willing to put a tenner on me being right :-)

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