Solving Proportions

Front

What is a proportion?

Back

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

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the terms and then solve for the variable.

Front

If 36 baseball cards cost $18, how much does 1 baseball card cost?

Back

1 baseball card costs $0.50.

Front

If Troy has $9, how many baseball cards can he buy if each costs $0.50?

Back

Troy can buy 18 baseball cards.

Front

What is the cross-multiplication method?

Back

The cross-multiplication method involves multiplying the numerator of one ratio by the denominator of the other ratio.

Front

Solve for x: 2/3 = x/12

Back

x = 8.

Front

What is the value of x in the proportion 5/x = 15/3?

Back

x = 1.

Front

If a recipe calls for 2 cups of flour for every 3 cups of sugar, what is the ratio of flour to sugar?

Back

The ratio of flour to sugar is 2:3.

Front

How do you check if two ratios are proportional?

Back

You can check if two ratios are proportional by cross-multiplying and seeing if the products are equal.

Front

Solve the proportion: 4/5 = x/25

Back

x = 20.