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Prealgebra

Chapter 9

PrealgebraChapter 9

Try It

9.1

$180

9.2

40

9.3

2

9.4

7

9.5

$950

9.6

$4,200

9.7

25

9.8

4

9.9

3

9.10

6

9.11

9, 15

9.12

27, 31

9.13

−8, −15

9.14

−29, 11

9.15

−4, 0

9.16

−2, −3

9.17

47, 48

9.18

−15, −16

9.19

31, 32, 33

9.20

−11, −12, −13

9.21

9 nickels, 16 dimes

9.22

17 nickels, 5 quarters

9.23

42 nickels, 21 dimes

9.24

51 dimes, 17 quarters

9.25

41 nickels, 18 quarters

9.26

22 nickels, 59 dimes

9.27

330 day passes, 367 tournament passes

9.28

112 adult tickets, 199 senior/child tickets

9.29

32 at 49 cents, 12 at 8 cents

9.30

26 at 49 cents, 10 at 21 cents

9.31
  1. 155°
  2. 65°
9.32
  1. 103°
  2. 13°
9.33

40°, 140°

9.34

25°, 65°

9.35

21°

9.36

56°

9.37

34°

9.38

45°

9.39

20°, 70°, 90°

9.40

30°, 60°, 90°

9.41

8

9.42

22.5

9.43

10

9.44

17

9.45

8

9.46

12

9.47

12 feet

9.48

8 feet

9.49
  1. cubic
  2. linear
  3. square
  4. linear
  5. square
  6. cubic
9.50
  1. cubic
  2. square
  3. cubic
  4. linear
  5. square
  6. linear
9.51
  1. 8 inches
  2. 3 sq. inches
9.52
  1. 8 centimeters
  2. 4 sq. centimeters
9.53
  1. 340 yd
  2. 6000 sq. yd
9.54
  1. 220 ft
  2. 2976 sq. ft
9.55

15 in.

9.56

9 yd

9.57

18 m, 11 m

9.58

11 ft , 19 ft

9.59

8 ft, 24 ft

9.60

5 cm, 4 cm

9.61

26 ft

9.62

29 m

9.63

30 ft, 70 ft

9.64

60 yd, 90 yd

9.65

13 sq. in.

9.66

49 sq. in.

9.67

8 ft

9.68

6 ft

9.69

14 in.

9.70

6 ft

9.71

13 in.

9.72

17 cm

9.73

14 ft

9.74

7 m

9.75

161 sq. yd

9.76

225 sq. cm

9.77

42 sq. cm

9.78

63 sq. m

9.79

40.25 sq. yd

9.80

240 sq. ft

9.81
  1. 31.4 in.
  2. 78.5 sq. in.
9.82
  1. 28.26 ft
  2. 63.585 sq. ft
9.83

17.27 ft

9.84

37.68 ft

9.85

30 cm

9.86

110 ft

9.87

28 sq. units

9.88

110 sq. units

9.89

36.5 sq. units

9.90

70 sq. units

9.91

103.2 sq. units

9.92

38.24 sq. units

9.93
  1. 792 cu. ft
  2. 518 sq. ft
9.94
  1. 1,440 cu. ft
  2. 792 sq. ft
9.95
  1. 216 cu. ft
  2. 228 sq. ft
9.96
  1. 2,772 cu. in.
  2. 1,264 sq. in.
9.97
  1. 91.125 cu. m
  2. 121.5 sq. m
9.98
  1. 389.017 cu. yd.
  2. 319.74 sq. yd.
9.99
  1. 64 cu. ft
  2. 96 sq. ft
9.100
  1. 4,096 cu. in.
  2. 1536 sq. in.
9.101
  1. 113.04 cu. cm
  2. 113.04 sq. cm
9.102
  1. 4.19 cu. ft
  2. 12.56 sq. ft
9.103
  1. 3052.08 cu. in.
  2. 1017.36 sq. in.
9.104
  1. 14.13 cu. ft
  2. 28.26 sq. ft
9.105
  1. 351.68 cu. cm
  2. 276.32 sq. cm
9.106
  1. 100.48 cu. ft
  2. 125.6 sq. ft
9.107
  1. 3,818.24 cu. cm
  2. 1,356.48 sq. cm
9.108
  1. 91.5624 cu. ft
  2. 113.6052 sq. ft
9.109

65.94 cu. in.

9.110

235.5 cu. cm

9.111

678.24 cu. in.

9.112

128.2 cu. in.

9.113

330 mi

9.114

7 mi

9.115

11 hours

9.116

56 mph

9.117
  1. r = 45 r = 45
  2. r = d t r = d t
9.118
  1. r = 65 r = 65
  2. r = d t r = d t
9.119

h=20h=20 h=2Abh=2Ab

9.120
  1. b = 4 b = 4
  2. b = 2 A h b = 2 A h
9.121
  1. t = 3 years t = 3 years
  2. t = I P r t = I P r
9.122
  1. r = 0.12 = 12% r = 0.12 = 12%
  2. r = I P t r = I P t
9.123
  1. y=1y=1
  2. y = 10 3 x 4 y = 10 3 x 4
9.124
  1. y = −1 y = −1
  2. y = 18 5 x 2 y = 18 5 x 2
9.125

b = Pac

9.126

c = Pab

9.127

y = 11 − 7x

9.128

y = 8 − 11x

9.129

y = 9 4 x 7 y = 9 4 x 7

9.130

y = 1 5 x 8 y = 1 5 x 8

Section 9.1 Exercises

1.

There are 30 children in the class.

3.

Zachary has 125 CDs.

5.

There are 6 boys in the club.

7.

There are 17 glasses.

9.

Lisa's original weight was 175 pounds.

11.

18%

13.

The original price was $120.

15.

4

17.

15

19.

5

21.

12

23.

−5

25.

18, 24

27.

8, 12

29.

−2, −3

31.

4, 10

33.

32, 46

35.

38, 39

37.

−11, −12

39.

25, 26, 27

41.

−11, −12, −13

43.

The original price was $45.

45.

Each sticker book cost $1.25.

47.

The price of the refrigerator before tax was $1,080.

49.

Answers will vary.

Section 9.2 Exercises

51.

8 nickels, 22 dimes

53.

15 dimes, 8 quarters

55.

12 dimes and 27 nickels

57.

63 dimes, 20 quarters

59.

10 of the $1 bills, 7 of the $5 bills

61.

10 of the $10 bills, 5 of the $5 bills

63.

16 nickels, 12 dimes, 7 quarters

65.

30 child tickets, 50 adult tickets

67.

110 child tickets, 50 adult tickets

69.

40 postcards, 100 stamps

71.

30 at 49 cents, 10 at 21 cents

73.

15 at $10 shares, 5 at $12 shares

75.

9 girls, 3 adults

77.

Answers will vary.

79.

Answers will vary.

Section 9.3 Exercises

81.
  1. 127°
  2. 37°
83.
  1. 151°
  2. 61°
85.

45°

87.

62.5°

89.

62°, 118°

91.

62°, 28°

93.

56°

95.

44°

97.

57°

99.

67.5°

101.

45°, 45°, 90°

103.

30°, 60°, 90°

105.

12

107.

351 miles

109.

15

111.

25

113.

8

115.

12

117.

10.2

119.

8

121.

5 feet

123.

14.1 feet

125.

2.9 feet

127.

Answers will vary.

Section 9.4 Exercises

129.

cubic

131.

square

133.

linear

135.
  1. 10 cm
  2. 4 sq. cm
137.
  1. 8 cm
  2. 3 sq. cm
139.
  1. 10 cm
  2. 5 sq. cm
141.
  1. 260 ft
  2. 3825 sq. ft
143.
  1. 58 ft
  2. 210 sq. ft
145.

24 inches

147.

27 meters

149.

23 m

151.

7 in., 16 in.

153.

17 m, 12 m

155.

13.5 m, 12.8 m

157.

25 ft, 50 ft

159.

7 m, 11 m

161.

26 in.

163.

55 m

165.

35 ft, 45 ft

167.

76 in., 36 in.

169.

30 sq. in.

171.

25.315 sq. m

173.

0.75 sq. ft

175.

8 ft

177.

23 in.

179.

11 ft

181.

28 cm

183.

17 ft

185.

6 m

187.

15 ft

189.

24 in.

191.

27.5 in.

193.

12 ft, 13 ft, 14 ft

195.

3 ft, 6 ft, 8 ft

197.

144 sq. ft

199.

2805 sq. m

201.

231 sq. cm

203.

28.56 sq. m

205.

13.5 sq. ft

207.

1036 sq. in.

209.

15 ft

211.

$24

213.

Answers will vary.

215.

Answers will vary.

Section 9.5 Exercises

217.
  1. 43.96 in.
  2. 153.86 sq. in.
219.
  1. 53.38 ft
  2. 226.865 sq. ft
221.

62.8 ft

223.

37.68 in.

225.

6.908 ft

227.

52 in.

229.

5.5 m

231.

24 ft

233.

6.5 mi

235.

16 sq. units

237.

30 sq. units

239.

57.5 sq. units

241.

12 sq. units

243.

67.5 sq. units

245.

89 sq. units

247.

44.81 sq. units

249.

41.12 sq. units

251.

35.13 sq. units

253.

95.625 sq. units

255.

187,500 sq. ft

257.

9400 sq. ft

259.
  1. 6.5325 sq. ft
  2. 10.065 sq. ft
261.

Answers will vary.

Section 9.6 Exercises

263.
  1. 9 cu. m
  2. 27 sq. m
265.
  1. 17.64 cu. yd.
  2. 41.58 sq. yd.
267.
  1. 1,024 cu. ft
  2. 640 sq. ft
269.
  1. 3,350.49 cu. cm
  2. 1,622.42 sq. cm
271.
  1. 125 cu. cm
  2. 150 sq. cm
273.
  1. 1124.864 cu. ft.
  2. 648.96 sq. ft
275.
  1. 262,144 cu. ft
  2. 24,576 sq. ft
277.
  1. 21.952 cu. m
  2. 47.04 sq. m
279.
  1. 113.04 cu. cm
  2. 113.04 sq. cm
281.
  1. 1,766.25 cu. ft
  2. 706.5 sq. ft
283.
  1. 14,130 cu. in.
  2. 2,826 sq. in.
285.
  1. 381.51 cu. cm
  2. 254.34 sq. cm
287.
  1. 254.34 cu. ft
  2. 226.08 sq. ft
289.
  1. 29.673 cu. m
  2. 53.694 sq. m
291.
  1. 1,020.5 cu. cm
  2. 565.2 sq. cm
293.
  1. 678.24 cu. in.
  2. 508.68 sq. in.
295.

37.68 cu. ft

297.

324.47 cu. cm

299.

261.67 cu. ft

301.

64,108.33 cu. ft

303.
  1. 31.4 cu. ft
  2. 2.6 cu. ft
  3. 28.8 cu. ft
305.

Answers will vary.

Section 9.7 Exercises

307.

612 mi

309.

7 mi

311.

6.5 hours

313.

3.6 hours

315.

60 mph

317.

80 mph

319.
  1. t = 5 t = 5
  2. t = d r t = d r
321.
  1. t = 8.5 t = 8.5
  2. t = d r t = d r
323.
  1. r = 68 r = 68
  2. r = d t r = d t
325.
  1. r = 64 r = 64
  2. r = d t r = d t
327.
  1. b = 14 b = 14
  2. b = 2 A h b = 2 A h
329.
  1. h = 30 h = 30
  2. h = 2 A b h = 2 A b
331.
  1. P = $19,571.43 P = $19,571.43
  2. P = I r t P = I r t
333.
  1. t = 6 years t = 6 years
  2. t = I P r t = I P r
335.
  1. y = 2 y = 2
  2. y = 12 2 x 3 y = 12 2 x 3
337.
  1. y = 13
  2. y = 7 − 3x
339.
  1. b = 90 − a
  2. a = 90 − b
341.

a = 180 − bc

343.

y = 15 − 8x

345.

y = −6 + 4x

347.

y = 7 4 x 3 y = 7 4 x 3

349.

y = 4 + x

351.

L = P 2 W 2 L = P 2 W 2

353.

d = C π d = C π

355.

L = V W H L = V W H

357.

104° F

359.

Answers will vary

Review Exercises

361.

Answers will vary.

363.

There are 116 people at the concert.

365.

His original weight was 180 pounds.

367.

38

369.

18, 9

371.

16 dimes, 11 quarters

373.

6 of $5 bills, 11 of $10 bills

375.

35 adults, 82 children

377.

3 of 26 -cent stamps, 8 of 41 -cent stamps

379.

132°

381.

33°, 57°

383.

73°

385.

30°, 60°, 90°

387.

15

389.

26

391.

8

393.

8.1

395.

6 feet

397.

cubic

399.

square

401.
  1. 8 units
  2. 3 sq. units
403.
  1. 140 m
  2. 1176 sq. m
405.
  1. 98 ft.
  2. 180 sq. ft.
407.

25 cm

409.

62 m

411.

24.5 in., 12.5 in.

413.

135 sq. in.

415.

600 sq. in.

417.

7 in., 7 in.

419.

17 ft., 20 ft., 22 ft.

421.

100 sq. ft.

423.

675 sq. m

425.
  1. 18.84 m
  2. 28.26 sq. m
427.

48 in.

429.

30 sq. units

431.

300 sq. units

433.

199.25 sq. units

435.
  1. 630 cu. cm
  2. 496 sq. cm
437.
  1. 15.625 cu. in.
  2. 37.5 sq. in.
439.
  1. 267.95 cu. yd.
  2. 200.96 sq. yd.
441.
  1. 12.76 cu. in.
  2. 26.41 sq. in.
443.
  1. 75.36 cu. yd.
  2. 100.48 sq. yd.
445.
  1. 753.6 cu. cm
  2. 477.28 sq. cm
447.

5.233 cu. m

449.

4.599 cu. in.

451.

1520 miles

453.

1.6 hours

455.
  1. t = 6.2 t = 6.2
  2. t = d r t = d r
457.
  1. b = 26 b = 26
  2. b = 2 A h b = 2 A h
459.
  1. P = $6000 P = $6000
  2. P = I ( r t ) P = I ( r t )
461.
  1. y = 4 y = 4
  2. y = 20 6 x 5 y = 20 6 x 5
463.

a = 90 − b

465.

y = 17 − 4x

467.

W = P 2 L 2 W = P 2 L 2

Practice Test

471.

−16

473.

7 quarters, 12 dimes

475.

38°

477.

48.3

479.

10

481.

127.3 ft

483.

2200 square centimeters

485.

282.6 inches

487.

1440

489.

31,400 cubic inches

491.

14.7 miles per hour

493.
  1. height = 52 height = 52
  2. h = 2 A b h = 2 A b
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