Writing & 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 unknown variable.

Front

If 20 pieces of candy cost $4, how much does each piece cost?

Back

Each piece costs $0.20.

Front

If Josh can buy 20 pieces of candy for $4, how many pieces can he buy for $12?

Back

He can buy 60 pieces.

Front

Bre spent $4.50 on 3 packs of valentines. How much did each pack cost?

Back

Each pack cost $1.50.

Front

Jackson buys 36 Pokemon cards for $18. How many cards can he buy for $9?

Back

He can buy 18 Pokemon 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

If a proportion is written as a/b = c/d, what does it mean?

Back

It means that the ratio of a to b is equal to the ratio of c to d.

Front

What is the first step in solving the proportion 3/x = 6/12?

Back

Cross-multiply to get 3 * 12 = 6 * x.

Front

What is the solution to the proportion 10/x = 5/2?

Back

The solution is x = 4.