To find 10% of a number we must find 1/10 of it.

One way to do this is to divide the number by 10.

To find 20% of a number we first find 10% and then double the result.

Example 1

Find 20% of 530.

Answer

First we find 10% which is 530 ÷ 10 = 53.

Then we double the result to get 53 x 2 = 106.

So 20% of 530 is 106.

Example 2

Find 20% of 7500.

Answer

First we find 10% which is 7500 ÷ 10 = 750.

Then we double the result to get 750 x 2 = 1500.

So 20% of 7500 is 1500.