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

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

Back

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

Front

Back

5x = 120.

Front

Back

Cross-multiply to get 6 * 30 = 15 * y.

Front

Back

8x = 648.

Front

If George pays $3 for every 5 donuts, what is the proportion to find out how much he pays for 25 donuts?

Back

Front

Back

y = 12.

Front

What does it mean if two ratios are equivalent?

Back

It means they represent the same relationship between quantities.