# Proportions

**Proportions:** A proportion is an equation that states that two ratios are equal.

**Equivalent Ratios:** If one of the numbers in a proportion is unknown, you can solve the proportion to find the unknown number. One way to solve a proportion is to use mental math to find an equivalent ratio.

Using Algebra: You can use the same methods you used to solve equations to solve proportions that have a variable in the numerator.

Every pair of ratios has two cross products. A cross product of two ratios is the product of the numerator of one ratio and the denominator of the other ratio.

**Cross Products Property:** The cross products of a proportion are equal.

Read the explanation below to learn more about proportions.

**Practice:** Answer the following exercises about proportions.