common error. (1 Viewer)

Pinkled

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6÷2(1+2)

Is the answer 9 or 1?
I reckon it's nine, but everybody else says its 1?
I'm using my bodmas and stuff
It's burning me.
 

nerdasdasd

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6÷2(1+2)

Is the answer 9 or 1?
I reckon it's nine, but everybody else says its 1?
I'm using my bodmas and stuff
It's burning me.
1, you do the brackets first
1= 6\(2x3)
 

Pinkled

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but then after you did brackets, you did 2(3), which is meant to come after dividing 6 with 2? o.o
 

Trebla

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6÷2(1+2)

Is the answer 9 or 1?
I reckon it's nine, but everybody else says its 1?
I'm using my bodmas and stuff
It's burning me.
The way I see it is
6 ÷ 2 x (1+2) = 6 ÷ 2 x 3 = 3 x 3 = 9
 

Sy123

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Well this is how i got my answer:
6÷2(1+2)
= 6÷2(3)
=3(3)
=9
?
Yes because BODMAS for multiplication and division should always go from left to right.

But the real question is. Why?

How can you 'prove' BODMAS?
 

Trebla

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Yes because BODMAS for multiplication and division should always go from left to right.

But the real question is. Why?

How can you 'prove' BODMAS?
lol wut it's a convention, you can't exactly prove it
 

nerdasdasd

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Damn I though you do the brackets first, and then times it by the 2
 

Sy123

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lol wut it's a convention, you can't exactly prove it
Yeah that's true, it seems to be the rules to follow when we are trying to symbolise what the author of an equation is trying to mean. And because we write from left to right, I guess that's why we only take multiplication and division from left to right?
 

Trebla

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Yeah that's true, it seems to be the rules to follow when we are trying to symbolise what the author of an equation is trying to mean. And because we write from left to right, I guess that's why we only take multiplication and division from left to right?
I think it is also there to remove ambiguity when it comes to arithmetic. You can probably define a number system that uses a different order of operations but the BODMAS system is the universal convention.
 

louielouiee

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I can't believe this is being debated.
 

D94

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Interestingly, on the fx-82AU PLUS calculator, if you type in 6÷2(1+2), you get 1, but if you type in 6÷2x(1+2), you get 9.
 

braintic

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Come on guys, simplify 6x÷2x. The answer has never been 3x^2.
 

Parvee

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This might be of relevance

 

seanieg89

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This is an obvious disadvantage of using that sign for division rather than

.

I don't think either answer is universally correct here as I have heard order of operations being taught as BOMDAS as well. When you want to be clear, use excessive brackets...it is your job as a student to make your meaning clear and unambiguous. (And the teachers jobs to make questions that are unambiguous!)

Being concise is nice but being clear should be of greater priority.

PS If I was given a set of exams to mark with this question in it, I would remove this question / give everyone the mark for it.
 
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RealiseNothing

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There's no consensus as far as I know, but I feel as if it should be 1. I think multiplication by juxtaposition should be enforced here.
 

Parvee

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I thought so too.
As far as I know there is no right answer
The only way to have a definite answer is to use brackets throughout
i.e. (6÷2)(1+2) or 6÷(2(1+2))
 

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