CHAPTER

8

Ratio and Proportion

Ratio

Aratiois a comparison of two numbers. For example, consider the state-

ment, ‘‘About 14 out of every 100 people in the United States do not have

health insurance.’’

A ratio can be expressed by a fraction or by using a colon. In the preceding

example, the ratio 10014 is the same as 14 to 100 or 14 : 100. Fractions are

usually reduced to lowest terms, so the ratio becomes 507 or 7 : 50.

It is important to understand that whatever number comes first in the ratio

statement is placed in the numerator of the fraction and whatever number

comes second in the ratio statement is placed in the denominator of the

fraction. In general, the ratio of a to b is written asab.

EXAMPLE

Find the ratio of 3 to 12.

SOLUTION

3to12¼

3

12

¼

1

4

153

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