Proportions: Word Problems

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 two ratios and set the products equal to each other.

Front

If 3 gallons of gas allows Ken to drive 78 miles, how many miles can he drive with 1 gallon?

Back

Ken can drive 26 miles with 1 gallon of gas.

Front

If 3 eggs are needed for 24 muffins, how many muffins can be made with 1 egg?

Back

8 muffins can be made with 1 egg.

Front

What is the ratio of boys to girls if there are 5 boys for every 4 girls?

Back

The ratio of boys to girls is 5:4.

Front

If there are 556 girls at a school with a boy-to-girl ratio of 5:4, how many boys are there?

Back

There are 695 boys at the school.

Front

What is the value of x in the proportion 3/4 = x/12?

Back

x = 9.

Front

How do you find an unknown in a proportion?

Back

You can find an unknown by cross-multiplying and solving for the variable.

Front

If a recipe requires 2 cups of flour for 3 servings, how much flour is needed for 9 servings?

Back

You need 6 cups of flour for 9 servings.

Front

What is the first step in solving a word problem involving proportions?

Back

Identify the ratios involved in the problem.