Page 378 - Basic College Mathematics with Early Integers

S E C T ION 5 .1 I RATIOS 355

3 1
In the example on the previous page, although = 1 , a ratio is a quotient of
2 2
two quantities. For that reason, ratios are not written as mixed numbers.

If a ratio contains decimal numbers or mixed numbers, we simplify by writing
the ratio as a ratio of whole numbers.

Example 3 Write the ratio of 2.6 to 3.1 as a fraction in simplest form. PRACTICE 3
Write the ratio of 3.9 to 8.8 as a
Solution: The ratio in fraction form is fraction in simplest form.
2.6
3.1
Now let’s clear the ratio of decimals.
#
2.6 2.6 2.6 10 2.6 10 26
= # 1 = # = = Simplest form
#
3.1 3.1 3.1 10 3.1 10 31
Work Practice 3

1 7
Example 4 Write the ratio of 1 to 2 as a fraction in simplest form. PRACTICE 4
5 10
2 13
1 Write the ratio of 2 to 1 as
1 3 15
5 a fraction in simplest form.
Solution: The ratio in fraction form is .
7
2
10
To simplify, remember that the fraction bar means division.
1
1 1 1
#
3 2
5 1 7 6 27 6 10 6 10 2 # # # 5 4
= 1 , 2 = , = # = = = Simplest form
#
7 5 10 5 10 5 27 5 27 5 # # # 9
3 3 3
2 1 1
10
Work Practice 4
Example 5 Writing a Ratio from a Circle Graph PRACTICE 5
Use the circle graph for
The circle graph at the right shows the part of a Work Example 5 to write the ratio of
car’s total mileage that falls into a particular cat- 4800 miles Medical work miles to total miles as a
egory.Write the ratio of family business miles to Vacation/ 150 miles fraction in simplest form.
total miles as a fraction in simplest form. other Visit friends
900 miles 1800 miles
Solution: Shopping School/
1800 miles church
family business miles 3000 miles
= 600 miles
total miles 15,000 miles Social/
recreational Family business
3000 1950 miles 3000 miles
=
15,000 Total yearly mileage: 15,000
1
3000 Sources: The American Automobile Manufacturers
= Association and The National Automobile
5 # 3000 Dealers Association.
1
1
= Answers
5
39 10 8
3. 4. 5.
Work Practice 5 88 7 25