Page 466 - Basic College Mathematics with Early Integers

S E C T ION 6 .1 I PERCENTS, DECIMALS, AND FRACTIONS 443

From Examples 7 and 12, we know that

100% = 1
Recall that when we multiply a number by 1, we are not changing the value of
that number. This means that when we multiply a number by 100%, we are not
changing its value but rather writing the number as an equivalent percent.

Examples Write each fraction or mixed number as a percent. PRACTICE 17–19
Write each fraction or mixed
9 9 9 100 900 number as a percent.
17. = # 100% = # % = % = 45%
20 20 20 1 20 1 7 1
17. 18. 19. 2
2 2 2 100 200 2 2 40 4
18. = # 100% = # % = % = 66 % 200
3 3 3 1 3 3 = 66.6. Thus,
3
1 3 3 100 300 200
19. 1 = # 100% = # % = % = 150% another way to write %
2 2 2 1 2 3
is 66.6%.
Work Practice 17–19

Concept Check Which digit in the percent 76.4582% represents
a. A tenth percent? b. A thousandth percent?
c. A hundredth percent? d. A whole percent?

1
Example 20 Write as a percent. Round to the nearest hundredth percent. PRACTICE 20
12
3
Solution: Write 17 as a percent. Round to
“approximately”
the nearest hundredth percent.
1 1 # 1 # 100 100
12 = 12 100%= 12 1 % = 12 %≠8.33%

8.333 L 8.33
12100.000
- 96
40
- 36
40
- 36
40
- 36
4

1
Thus, is approximately 8.33%.
12
Work Practice 20
Answers
1
17. 50% 18. 17 % 19. 225%
2
20. 17.65%
Concept Check Answers
a. 4 b. 8 c. 5 d. 6