This worksheet is about keeping pairs of numbers in the same ratio.

If two quantities are in direct proportion, the ratio between corresponding values will always be the same.

a | = | 1 | 2 | 3 | 4 | 5 |

b | = | 1.5 | 3 | 4.5 | 6 | 7.5 |

In this table the ratio between a and b can be found by **dividing** the value of b by its corresponding value of a.

3 ÷ 2 = 1.5

4.5 ÷ 2 = 1.5

Now we know the ratio between the two values we can find b** **by **multiplying a** by 1.5.

For example, if a = 6 then b = 1.5 × 6 = 9

We can also use this **ratio** to find the value of** a** if we know what **b** is.

For example if b = 15, then a = 15 ÷ 1.5 = 10

As we are doing the **inverse** we divide.