Science

Ratio and Proportion

A ratio is a way of comparing the sizes of two or more quantities.

Writing a Ratio in its Simplest Form

Ratios can be simplified, like fractions by dividing each number in the ratio by

the highest common factor.

Example

The ratio of boys to girls in a class is 25:30. Simplify this ratio.

1. The highest common factor of both 25 and 30 is 5.

2. 25/5 = 5 and 30/5 = 6

Therefore the simplified ratio is 5:6. There are 5 boys present in this class for

every 6 girls.

Steps 1. Find the highest common factor of all the numbers in the ratio. A ratio may consist of 2 or more numbers! 2. Divide each number in the ratio by the highest common factor determined in step 1.
3. These new values make up your simplified ratio. Just put the numbers together with a colon ( : ) in between. Remember to keep the values in the ratio in the correct order. For example if the question gives you a ratio of boys to girls, make sure the simplified value of boys goes before the simplified value for girls when writing out the ratio. |

Dividing in a Ratio

1. Simplify the ratio 63:49 2. Simplify the ratio 18:81 3. The ages of Anna and Ben are in the ratio of 24:36. Simplify this ratio 4. There are 18 girls and 21 boys in a class. What is the ratio of girls to boys? Give your answer in the simplest form. 5. In a retail workspace, there are 344 right handed people and 33 left handed people. Find the ratio of right handed to left handed people. Give your answer in the simplest form. |

Related Topics

Speed-distance-and-time Fractions-de-percentages Decimals-and-fractions