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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. you have to use the bodmas rule, as my old maths teacher from scandanavia used to say.

brackets, other, division, multiplication, addition and then subtraction.

So in that order: 48/2*12

next step division, so: 24*12 = 288
2. (Original post by DanielleT192)
Also, you were set on the answer being 288 but now you're swaying towards the answer of 2, which shows that you're unsure of your answer too.
Whatever gives you that idea? Which post? Nothing could be further from the truth.
3. (Original post by Good bloke)
Whatever gives you that idea? Which post? Nothing could be further from the truth.
I know I was about to edit that part as I hadn't realised there were two purple usernames. Lol damn.
4. (Original post by DanielleT192)
real proof, i.e. from a maths teacher/tutor
5. (Original post by DFranklin)
Except I doubt you'd find a single university level textbook, or lecturer, who agrees that 3x/2y = 3xy/2.

At some point you need to take account of what mathematicians really do, rather than some set of rules you learned at GCSE.
6. (Original post by DFranklin)
Except I doubt you'd find a single university level textbook, or lecturer, who agrees that 3x/2y = 3xy/2.

At some point you need to take account of what mathematicians really do, rather than some set of rules you learned at GCSE.

This has nothing to do with GCSE - in fact the rule (BODMAS) you learn there is dangerously misleading.

The rules of notation I'm describing are universal, its what mathematicians really do, and are based on university level experience. You parse left to right when dealing with operators of equal precedence. Full stop, end of discussion.

That said, noone uses the ÷ symbol and when writing on paper or a whiteboard the vertical position of the symbols would make the meaning of the notation clear.

7. mind = BLOWN
8. 48/2(9+3)= 2
If it were
(48/2)(9+3)= 288
9. (Original post by Planto)
Well people are trying to back up their points and the topic seems to have turned into an unwanted debate. What would your answer be?
10. wow really being neg repped for my answer okay .....
11. (Original post by DFranklin)
Except I doubt you'd find a single university level textbook, or lecturer, who agrees that 3x/2y = 3xy/2.

At some point you need to take account of what mathematicians really do, rather than some set of rules you learned at GCSE.
This can only be true, If y=1
12. (Original post by Prince of Zamunda)

mind = BLOWN
I sat in on a technical product pitch from TI once.

Boooooooooring.
13. (Original post by DanielleT192)
Well people are trying to back up their points and the topic seems to have turned into an unwanted debate. What would your answer be?
He gave it at post 175.
14. (Original post by Get me off the £\?%!^@ computer)
I quoting myself because my post got swamped by all the garbage. (I'm not referring to your post, just all the others )

The trouble with threads like this is that being about simple things they attract all the simple people.

Lots of posters here don't even understand precedence and most of those who do understand precedence don't realise that it's not the issue here.

As far as I can see only DFranklin and I actually understand what this thread is really about.

Last point:

Casio fx991es says 288.

Casio fx991es plus say 2.
What on EARTH does the order that various calculators parse symbols have to do with which way is correct.

In any case, if we are playing the calculator game:
The equation gives 2 on a TI-82, but 288 on a TI-83.

Oh look....

The correct order of precedence is left to right for equal priority operators. This is not just "technically" correct but how it is done, correctly, in practice.

as I've said however, normally you would not use the divide symbol, instead using fractional notation, and the vertical position of the elements of the equation would make things clear (vertical position effectively acts like parentheses, similarly to the way the top bar of a route symbol does)
15. (Original post by powerafcw)
48/2(9+3)= 2
If it were
(48/2)(9+3)= 288
wrong. You do multiplication and division left to right,

48/2(9+3)
= 48/2(12)
= 24(12)
= 288.
16. (Original post by Good bloke)
Oh dear!
Gosh this is why I'm not doing a maths degree! Haha
17. (Original post by DanielleT192)
Well people are trying to back up their points and the topic seems to have turned into an unwanted debate. What would your answer be?
Its been explained to you several times what the rules are and how they apply.

Which part do you disagree with - the rule that multiplication and division are of equal precedence, the rule that you deal with equal precedence operators left to right, or that these rules apply to give 288?

PS: I have a feeling its a wooly "doing the multiplication first just FEELS more normal"
18. 288! 288! 288!
19. 288 .. It has to be assumed that the equation is (48/2)*12 because of BIDMAS.
20. (Original post by DFranklin)
Except I doubt you'd find a single university level textbook, or lecturer, who agrees that 3x/2y = 3xy/2.

At some point you need to take account of what mathematicians really do, rather than some set of rules you learned at GCSE.
Except that literally every single expert, textbook etc would agree that 3x/2y = 3xy/2 when notated exactly like that

However textbooks dont use normal text to write equations. so it would be written like this

3x
---y
2

NOT

3x
----
2y

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