# How to Apply ratio and Proportion in maths

## Contents

A ratio is a number that relates two quantities or measures within a given situation in a multiplicative relationship.

Ratios show comparisons of a part to a whole. For example, the number of girls in a class to number of students in a class. It is much like fractions. So fractions are also ratios. Percentages are also ratios. Probabilities are also ratios. Rates are also ratios.

Ratios show comparison of one part of a whole to another part of the same whole. Example: ratio can show the number of girls in a class to number of boys in the same class.

Relationship between two units of measure are also rates or ratios. Example, inches per foot.

## Proportion

Proportion is a statement of equality between two ratios.

Example 1: If 4 boats can carry 20 passengers, then 2 boats of the same size will carry 10 passengers. And one boat can carry 5 passengers.

A ratio compares two numbers or groups of objects.

Ratios can be written in the following ways: 4 to 20, 4:20, and 4/20. They are read as “4 to 20”.

Each ratio show the same comparison.

Exercise 2.

Danny bought a pineapple that weighed 2 pounds. The vendor sold her the pineapple for \$12.00 dollars. How much would two pineapples that weigh a total of 5 pounds cost?

\$12.00 for 2 pounds of pineapple
12: 2