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.
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.