Back to basics - help with basic arithematics (BODMAS/PEDMAS Rule)

[rifaan]

I know this is a very easy question, but I have been having some disagreements with my friends over the answer for this question. Please help.

Question 6 ÷ 2(1+2)=?

Is the correct answer

a) 9 Do we first divide 6 by 2 and multiply with the resulting 3 in the bracket to get this 9

or

b) 1 Do we first deal with the bracket (1+2)=3, then multiply by 2 [i.e. 2(3) = 6] and then divide the original 6 with the resulting 6 to get 1.

 

[Deleted member 4993]

I know this is a very easy question, but I have been having some disagreements with my friends over the answer for this question. Please help.

Question 6 ÷ 2(1+2)=?

Is the correct answer

a) 9 Do we first divide 6 by 2 and multiply with the resulting 3 in the bracket to get this 9 .... correct answer but incorrect process

or

b) 1 Do we first deal with the bracket (1+2)=3, then multiply by 2 [i.e. 2(3) = 6] and then divide the original 6 with the resulting 6 to get 1.

6 ÷ 2(1+2) = 6 ÷ 2 * 3 = 3 * 3 = 9

 

[Ishuda]

I know this is a very easy question, but I have been having some disagreements with my friends over the answer for this question. Please help.

Question 6 ÷ 2(1+2)=?

Is the correct answer

a) 9 Do we first divide 6 by 2 and multiply with the resulting 3 in the bracket to get this 9

or

b) 1 Do we first deal with the bracket (1+2)=3, then multiply by 2 [i.e. 2(3) = 6] and then divide the original 6 with the resulting 6 to get 1.

As Subhotosh Khan indicates
B=Brackets [or, same thing, P=Parenthesis]
O=Order [or, same thing, E=Exponent]
DM=Division & Multiplication, left to right
AS=Addition&Subtraction, left to right

6 ÷ 2(1+2)
B: = 6 ÷ 2(3)
MD: = 3(3)
MD: = 9

 

[ksdhart]

Honestly, I blame the school system for not teaching this concept well enough. It's an extremely crucial thing to know. And yet so many people fail spectacularly at it. The error I see most commonly is that people get hung up on the specific order of the operations. They miss the fact that Multiplication and Division have the same priority, as do Addition and Subtraction. Add in the confusion over which one is right - i.e. is it PEMDAS or BODMAS? - and it's easy to see why everybody's confused and seemingly can't do basic math.

 

[Steven G]

Honestly, I blame the school system for not teaching this concept well enough. It's an extremely crucial thing to know. And yet so many people fail spectacularly at it. The error I see most commonly is that people get hung up on the specific order of the operations. They miss the fact that Multiplication and Division have the same priority, as do Addition and Subtraction. Add in the confusion over which one is right - i.e. is it PEMDAS or BODMAS? - and it's easy to see why everybody's confused and seemingly can't do basic math.

The school teachers have trouble teaching this correctly because either they do not really understand it them selves and/or they have no interest in their students learning.
Personally I never mention PEMDAS or BODMAS (actually never heard of this one!) but rather I teach how to determine terms and factors.

 

[pka]

Honestly, I blame the school system for not teaching this concept well enough. It's an extremely crucial thing to know. And yet so many people fail spectacularly at it. The error I see most commonly is that people get hung up on the specific order of the operations. They miss the fact that Multiplication and Division have the same priority, as do Addition and Subtraction. Add in the confusion over which one is right - i.e. is it PEMDAS or BODMAS? - and it's easy to see why everybody's confused and seemingly can't do basic math.

The problem is: THERE IS NO CORRECT WAY TO TEACH IT.
It is all bogus. Please, please look at this. Watching those you will see the is no agreement.

Its like Jomo said, it is best to never teach things like FOIL What a stupid idea.
There is a method of learning that always works: practice, practices, and more practice.

As far as order of operations goes, it changes from language to language. Sometimes subject to subject, or textbook to textbook.

NO ONE WAY IS RIGHT!

 

[springer5]

The problem is: THERE IS NO CORRECT WAY TO TEACH IT.
It is all bogus. Please, please look at this. Watching those you will see the is no agreement.

Its like Jomo said, it is best to never teach things like FOIL What a stupid idea.
There is a method of learning that always works: practice, practices, and more practice.

As far as order of operations goes, it changes from language to language. Sometimes subject to subject, or textbook to textbook.

NO ONE WAY IS RIGHT!

If that's the case (and I accept your superior knowledge on the subject) then it can only mean that any given arithemtic problem involving basic arithmetic operators can have as many solutions as you can find by changing the order of operations in as many ways as you can find.

Every arithemtic question has no 'correct' answer.

Is that what you're saying? I can't believe it is.

I've just posted a similar question to the OPs on a new thread. My maths book comes up with one answer and I omce up with another. So according to your post w'ere both right (plus any number of other solutions I could find by ording the perations diferently, about 4 or 5 at first glance)

 

[pka]

Every arithmetic question has no 'correct' answer.
Is that what you're saying? I can't believe it is.

I did not say that. Of course every simple arithmetic question question can be answered. (Lets leave Goedel out).

I said that there is no correct way to teach it. AND we must be clear on the context of the question.