Solving Proportions With 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 terms and then solve for the unknown variable.

Front

What does it mean to cross-multiply?

Back

Cross-multiplying involves multiplying the numerator of one ratio by the denominator of the other ratio.

Front

If 3/4 = x/12, what is x?

Back

x = 9.

Front

What is the formula for finding a missing value in a proportion?

Back

If a/b = c/d, then ad = bc.

Front

In the problem, 'If Shane can bake 120 dozen cookies in five days, how many days would it take to bake 800 dozen cookies?', what is the first step to solve it?

Back

Set up the proportion: 120/5 = 800/x.

Front

What is the solution to the proportion 120/5 = 800/x?

Back

x = 34 days.

Front

Danielle used 8 centimeters of tape to wrap 4 presents. How do you set up the proportion to find how many presents she can wrap with 30 centimeters?

Back

Set up the proportion: 8/4 = 30/x.

Front

What is the solution to the proportion 8/4 = 30/x?

Back

x = 15 presents.

Front

What is a ratio?

Back

A ratio is a comparison of two quantities by division.