# The Order of Operations (BIDMAS)

There is a correct order to do calculations in, this is so everyone does calculations in the same way. When we do calculations we need to do them in the correct order.

The order of operations is:
1) Brackets
2) Indices
3) Dividing and Multiplying

Dividing and Multlipying are in the same line - they can be done in any order.
Adding and Subtracting are also on the same line - they can be done in any order but it is usually easier to do them from left to right.

Example 1:
3 + 5 × 4

We have no brackets and no indices.
5 × 4 = 20
So we now have 3 + 20
3 + 20 = 23

3 + 5 × 4 = 23

Example 2:
(2 + 7)² - 11

2 + 7 = 9
So we now have 9² - 11
Next is the indices
9² = 81
So now we have 81 - 11
81 - 11 = 70

(2 + 7)² - 11 = 70

Example 3:
30 - 36 ÷ 3 + 5

We have no brackets or indices, so we start with the division
36 ÷ 3 = 12
So we now have 30 - 12 + 5
Next we have the addition and subtraction. It is easiest to do this from left to right (If we did the addition first it would be -12 + 5 = -7).
30 - 12 = 18
18 + 5 = 23

30 - 36 ÷ 3 + 5 = 23

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