Ratio and Proportion

A ratio is a comparison of two or more quantities of the same kind, expressed as a fraction or with a colon (e.g., 3:4).

To simplify a ratio, divide both terms by their greatest common divisor (GCD). For example, to simplify 8:12, divide both by 4 to get 2:3.

Two ratios are equivalent if they represent the same relationship between quantities. For example, 1:2 is equivalent to 2:4.

This indicates that the two ratios are equivalent, meaning they represent the same relationship.

1:4 (since 30 minutes is 1/4 of 2 hours).

The ratio of girls to total students is 4:7 (20 girls out of 35 total students).

The ratio of boys to girls is 5:2.

A proportion is an equation that states that two ratios are equal. For example, 1:2 = 2:4 is a proportion.

The unit rate is a ratio that compares a quantity to one unit of another quantity, such as miles per hour.

To find the total number of students from a ratio, add the parts of the ratio together. For example, in a ratio of 3:4, the total is 3 + 4 = 7 parts.