Simplifying without a calculator

[wolfcry044]

I am trying to simplify 35-14 divided by 2+64.

However, the math book I'm using of course does not tell me what to do in this situation without a calculator. If I try to do the addition and subtraction and then divide them it gives me the wrong answer. If I do it across the board with a calculator it comes up with the right answer.

I can't figure how I'm supposed to mentally solve an equation like that without doing the addition and subtraction before dividing. : /

 

[Deleted member 4993]

I am trying to simplify 35-14 divided by 2+64.

However, the math book I'm using of course does not tell me what to do in this situation without a calculator. If I try to do the addition and subtraction and then divide them it gives me the wrong answer. If I do it across the board with a calculator it comes up with the right answer.

I can't figure how I'm supposed to mentally solve an equation like that without doing the addition and subtraction before dividing. : /

Is your problem:

\(\displaystyle 35 - 14 \div 2 + 64 \ = \ ??\)

or

\(\displaystyle \dfrac{35 - 14}{2 + 64}\ = \ ??\)

 

[ClaireWu]

I am trying to simplify 35-14 divided by 2+64.

However, the math book I'm using of course does not tell me what to do in this situation without a calculator. If I try to do the addition and subtraction and then divide them it gives me the wrong answer. If I do it across the board with a calculator it comes up with the right answer.

I can't figure how I'm supposed to mentally solve an equation like that without doing the addition and subtraction before dividing. : /

Always follow this rule: B O D M A S : priority is given to bracketed item then division or multiplication and lastly addition or subtraction
(the O has no meaning here...it is used to make a word for memorising)

if it is 35-14/2+64 then you do the 14/2 and followed by the addition and subtraction

if it is (35-14)/(2+64) then you do the bracketed (35-14) and (2+64) first and then followed by the division

 

[HallsofIvy]

I am trying to simplify 35-14 divided by 2+64.

However, the math book I'm using of course does not tell me what to do in this situation without a calculator. If I try to do the addition and subtraction and then divide them it gives me the wrong answer. If I do it across the board with a calculator it comes up with the right answer.

I can't figure how I'm supposed to mentally solve an equation like that without doing the addition and subtraction before dividing. : /

It would be extremely difficult for any one to "mentally solve an equation like that without doing the addition and subtraction before dividing."

Why in the world would you want to? By the rules of arithmetic, as ClaireWu said, you always do the addition and subtraction before dividing!

 

[wolfcry044]

Thank you, I figured it out before reading this. I was looking at it wrong. I had to divide the middle numbers and then do the addition/subtraction.