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When there is more than one operation in a question, you need to remember the order in which operations are carried out. This can be summarised by BODMAS:
- Brackets first
- O
- Divide
- Multiply
- Add
- Subtract
If you see two of the same operation you just do them in the order they appear (left to right).
Example Question
Below are three examples of BODMAS used in a question.
| (a) 3 + 4 × 5 = 3 + 20 = 23 |
(Multiply before Add)
| | (b) 10 ÷ ( 2 + 3 ) = 10 ÷ 5 = 2 |
(Brackets before Division)
| | (c) 20 ÷ 2 ÷ 2 = 10 ÷ 2 = 5 |
(do operations left to right)
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Practice Questions
Work out the answer to each of these questions then click on the button marked
to see whether you are correct.
(a) What is 3 + 16 × 2 ?
(b) What is 15 ÷ (2 + 3) ?

Exercises
Work out the answers to the questions below and fill in the boxes. Click on the
button to find out whether you have answered correctly. If you are right
then will appear and you should move on to the next
question. If appears then your answer is wrong. Click
on to clear your original answer and have another go.
If you can't work out the right answer then click on
to see
the answer.
Question 1
Use mental arithmetic to answer these questions (do not use a calculator).
Question 2
Use BODMAS to work out whether these statements are TRUE or FALSE.
Question 3
Work out the answers to the following questions (without a calculator).
Question 4
A pupil works out 200 ÷ 4 by this method:
200 ÷ 2 = 100
100 ÷ 2 = 50
So 200 ÷ 4 = 50. This works because doing (÷2) twice is the same as doing (÷4).
Use similar methods to find the answers to these questions (not a calculator).
Produced by Al Reynolds for CIMT
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