For full tracking and unlimited access to thousands of activities

When you are working something out that involves more than one operation, the order in which it is carried out matters.

 

The agreed order is:

      Brackets
      Powers or indices
       Division and Multiplication
      Addition and subtraction

 

This can be remembered using the word: BIDMAS  or BODMAS   

 

However, remember that multiplication and division are equally important, so in a calculation just involving multiplication and division, you carry this out from left to right.  Similarly with addition and subtraction.



Examples

6 + 9 ÷ 3  The first operation to do is division because we have no brackets or indices.

6 + 3 = 9

 


(6 + 9) ÷ 3  This time, we have brackets, so do those first.

15 ÷ 3 = 5

 


15 - 4 × 2  This time, we have no brackets, indices or division, so we multiply first.

15 - 8 = 7

 


(15 - 4) × 2  Here, we do brackets first.

11 x 2 = 22

 


4 × 32 = 4 × 9 = 36 This time, we do the power first.

4 x 9 = 36

 


(4 × 3)2 This one needs us to do the brackets first.

122 = 144

 

14 - 4 + 5   This time, we have only addition and subtraction.  This means that they are equally important, so we do it left to right.

10 + 5 = 15

 

That's lots of examples to work through. Hopefully, they have given you a good overview of how to tackle the order of operations.

 

Are you ready to have a go at some questions yourself?

 

thinking child

10 questions