CHAPTER
Chapter Review
6
6-1 Relating Decimals, Fractions, and Percents
Compare. Write , , or .
1
1. 5
25%
2. 0.42
41%
3. 0.075
1
72%
6-2 Estimating with Percents
Estimate.
4. 75% of 195
5. 49% of 19
6. 40% of 219
7. A grade school has 407 students. Approximately 41% of the students walk
to school. Estimate how many students walk to school.
6-3 Finding Percents
Find each number to the nearest tenth.
8. What is 35% of 340?
9. What percent of 80 is 18?
10. A son earns 62% of what his father earns. If the son earns $52,000, how
much does his father earn to the nearest dollar?
6-4 Finding a Number When the Percent Is Known
Find each number to the nearest whole number.
11. 13 is 52% of what number?
12. 11 is 12.5% of what number?
13. An elephant can run 36% as fast as a cheetah. If a chetah can run 70 mph,
how fast can an elephant run to the nearest whole number?
14. A quarterback completed 54% of his passes for the season. If he threw
369 passes in the season, how many passes did he complete to the
nearest whole number?
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Holt Mathematics
CHAPTER
Chapter Review
6
6-1 Relating Decimals, Fractions, and Percents
Compare. Write , , or .
1
1. 5
25%
2. 0.42
41%
3. 0.075
1
72%
6-2 Estimating with Percents
Estimate.
4. 75% of 195
150
10
5. 49% of 19
6. 40% of 219
85
7. A grade school has 407 students. Approximately 41% of the students walk
to school. Estimate how many students walk to school.
160
6-3 Finding Percents
Find each number to the nearest tenth.
8. What is 35% of 340?
119
9. What percent of 80 is 18?
22.5%
10. A son earns 62% of what his father earns. If the son earns $52,000, how
much does his father earn to the nearest dollar?
$83,871
6-4 Finding a Number When the Percent Is Known
Find each number to the nearest whole number.
11. 13 is 52% of what number?
25
88
12. 11 is 12.5% of what number?
13. An elephant can run 36% as fast as a cheetah. If a chetah can run 70 mph,
how fast can an elephant run to the nearest whole number?
25 mph
14. A quarterback completed 54% of his passes for the season. If he threw
369 passes in the season, how many passes did he complete to the
nearest whole number?
199
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All rights reserved.
132
Holt Mathematics
CHAPTER 6 REVIEW CONTINUED
6-5 Percent Increase and Decrease
Find each percent increase or decrease to the nearest percent.
15. From 32 to 20
16. From 65 to 130
17. From 142 to 86
18. From 17 to 56
19. A television was marked 30% off. The original price was $1,999. What was
the reduced price of the television?
20. Sales at a grocery store increase 22% during the month of December.
If the monthly sales are usually $300,000, how much are the sales in
December?
6-6 Applications of Percents
Find each commission or sales tax to the nearest cent.
21. total sales: $16,000
commission: 3.75%
22. total sales: $21,500
sales tax: 6.75%
23. A realtor earns a 3% commission on each house sold. If a realtor sold two
houses for $179,500 and $214,000, what was the total commission?
24. A car salesman earned $918.75 from a commission rate of 3.75% on the
sale of a car. What was the price of the car?
6-7 Simple Interest
Find the interest and total amount to the nearest tenth.
25. $650 at 4.5% per year for 4 years
26. $2,250 at 3% per year for 2 years
27. John borrowed $25,000 to fix his porch. The bank charged him a simple
interest rate of 7.75%. How much will John owe if he pays the bank back in
5 years?
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133
Holt Mathematics
CHAPTER 6 REVIEW CONTINUED
6-5 Percent Increase and Decrease
Find each percent increase or decrease to the nearest percent.
15. From 32 to 20
16. From 65 to 130
decrease, 37.5%
increase, 100%
17. From 142 to 86
18. From 17 to 56
decrease, 39%
increase, 229%
19. A television was marked 30% off. The original price was $1,999. What was
the reduced price of the television?
$1,399.30
20. Sales at a grocery store increase 22% during the month of December.
If the monthly sales are usually $300,000, how much are the sales in
December?
$366,000
6-6 Applications of Percents
Find each commission or sales tax to the nearest cent.
21. total sales: $16,000
commission: 3.75%
$600
22. total sales: $21,500
$1,451.25
sales tax: 6.75%
23. A realtor earns a 3% commission on each house sold. If a realtor sold two
houses for $179,500 and $214,000, what was the total commission?
$11,805
24. A car salesman earned $918.75 from a commission rate of 3.75% on the
sale of a car. What was the price of the car?
$24,500
6-7 Simple Interest
Find the interest and total amount to the nearest tenth.
25. $650 at 4.5% per year for 4 years
$117; $767
26. $2,250 at 3% per year for 2 years
$135; $2,385
27. John borrowed $25,000 to fix his porch. The bank charged him a simple
interest rate of 7.75%. How much will John owe if he pays the bank back in
5 years?
$34,687.50
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133
Holt Mathematics
CHAPTER
Big Ideas
6
Answer these questions to summarize the important concepts from
Chapter 6 in your own words.
3
1. Explain how to convert 8 to a percent.
2. Explain how to solve “34 is 25% of what number?”.
3. Explain how to find the percent increase or decrease from 200 to 145.
4. Explain how to find the interest and total amount of $400 at 7.5% per year
for 8 years.
For more review of Chapter 6:
• Complete the Chapter 6 Study Guide and Review on pages 312–314 of
your textbook.
• Complete the Ready to Go On quizzes on pages 292 and 308 of your
textbook.
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
134
Holt Mathematics
CHAPTER
Big Ideas
6
Answer these questions to summarize the important concepts from
Chapter 6 in your own words.
3
1. Explain how to convert 8 to a percent.
First convert the fraction to a decimal by dividing the numerator by
3
the denominator: 8 3 8 0.375. Then convert the decimal to a
percent by multiplying by 100 and inserting a percent symbol:
0.375 100 37.5%.
2. Explain how to solve “34 is 25% of what number?”.
Set up an equation to find the number: 34 25% n. Change the
percent to a decimal: 34 0.25n. Divide both sides by 0.25:
0.25n
34
. Simplify: 136 n. 34 is 25% of 136.
0.25
0.25
3. Explain how to find the percent increase or decrease from 200 to 145.
This is a percent decrease because 145 is less than 200. First find
the amount of change: 200 145 55. Think: What percent is 55 of
55
amount of increase . Find the decimal
200? Set up the ratio: ——————————
200
55
original amount
0.275. Write as a percent: 0.275 27.5%. From 200 to
form: 200
145 is a 27.5% decrease.
4. Explain how to find the interest and total amount of $400 at 7.5% per year
for 8 years.
Substitute known values into the formula I Prt, use 0.075 for
7.5%: I 400 0.075 8. Solve: I $240. Find the total amount
using the formula: P I A: 400 240 $640.
For more review of Chapter 6:
• Complete the Chapter 6 Study Guide and Review on pages 312–314 of
your textbook.
• Complete the Ready to Go On quizzes on pages 292 and 308 of your
textbook.
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
134
Holt Mathematics