Chapter 1 Answers
Practice 1-1
Practice 1-5
1. 7 + x 2. 3p 3. 10 - m 4. 7 - n
5. 2q 6. m + 3 7. 8 divided by a 8. 10 less than s
9. 13 more than x 10. 2 more than the product of a and b
11. 8 - n 12. 4 + n 13. 2n 14. 3 + n 15. 10 1 n
15
16. n - 12 17. c = 24.95s 18. g = 30t 19. m = 0.10d
20. n = 48 - g 21. c = 8p 22. c = 32.95p
23–28. Choice of variables may vary.
1.
Practice 1-3
1. rational, real 2. rational, real 3. natural, whole, integers,
rational, real 4. irrational, real 5. irrational, real
6. integers, rational, real 7. rational, real 8. natural, whole,
integers, rational, real 9. true 10. false; -2 11. true
12. false; 7 3 2 = 14 13. . 14. , 15. , 16. = 17. .
18. , 19. 289 , 222 , 287 20. 23 12 , 23.45, 23 94
25
25
21. 2 1 , 2 1 , 2 1 22. 21 79 , 21 3 , 21.7 23. 2 7 , 2 3 , 2 2
3
4
5
4
8
4
3
24. 2 5 , 2.7, 2 3 25. whole 26. rational 27. whole
8
4
3
28. irrational 29. 10
30. 327 31. 3.46 32. 21
33. $154.23, 0.0375, 30 , $.48, 0.055, and 3 1 are rational
2
365
and real; $8000 and $1540 are whole, integers, rational, and real.
Practice 1-4
1. p = 9t 2. c = 13n 3. m = 5n + 20
4. c = 2.50n + 7.50 5. number of hours; amount earned
6. number of people; cost 7. number of minutes; volume
8. price; number of people 9. 96; 120; b = 24c
10. $.90; $1.00; c = 0.10m + 0.50
32
Answers
Hourly Pay
(dollars)
Speed of Winds in Some U.S. Cities
100
90
80
70
60
0
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1. 52 2. 2 3. 38 4. 4 5. 18.9 6. 87 7. 25 8. 7 9. 2
10. 1 11. 9 12. 30.4 13. 19 14. 5 15. 2 16. 6 17. 26
18. 29 19. 31 20. 88 21. 14.18 22. 85 23. 28 24. 12
25. 26 26. 5 27. 55 28. 56 29. 72 30. 60 31. 40 32. 2
33. 11 34. 4 35. 131 36. 141 37. 33 38. 16 39. 22
40. 12 41. 2 42. 1 43. 56 44. $33.95 45. $63.34 46. 24
47. 2.25 48. 0 49. 99 50. 5 51. 6
2.
60 65 70 75
Height (in.)
9.0 9.5 10.0 10.5 11.0 11.5 12.0 12.5 13.0
Average Speed (mi/h)
3. positive correlation 4. negative correlation
5. no correlation 6. no correlation 7. positive correlation
8. no correlation; a person’s age is not related to the number
of pets he/she may have. 9. negative correlation; the more
times you brush, the fewer the cavities you are likely to have.
10. positive correlation; the more rainy days, the more
umbrellas are likely to be sold. 11a. Each point represents
one infant’s age and weight. 11b. There will be points with
the same y-coordinate. 11c. The points will have the same
x-coordinate. 11d. Yes, there is a positive correlation. Weight
increases with age.
Practice 1-6
1. 2.5; 2; 1; median 2. $120.50; $123; no mode; mean
3. $31.16; $31.25; no mode; median 4. 7.11; 8; 8 and 10; median
5. $2.81 6. 3
7. 4.8 1 1.6 41 5.2 1 x 5 3.7; 3.2
102 1 21 1 x 5 88; 173
8. 40 1 98 1 94 1
6
9. 100 1 172 1585 1 92 1 x 5 115; 126
10. 25.6 1 19.34 1 19 1 x 5 24; 32.1
11. yes; The range is 0.9 fl oz. 12. no; The mean was 6.7 ppm.
13. 98
Algebra 1 Chapter 1
© Pearson Education, Inc., publishing as Pearson Prentice Hall.
Practice 1-2
8.50
8.00
7.50
7.00
6.50
6.00
5.50
5.00
0
Highest Speed
(mi/h)
t = number of tickets, c = total cost;
h = number of hours, d = distance;
h = number of hours, p = total pay;
c = change, a = total cost;
d = number of days, l = length;
r = miles traveled, t = miles remaining
23. c = 3.50t 24. d = 55h 25. p = 5h 26. a = 10 - c
27. l = 0.45d 28. r = 500 - t
Height and Hourly
Pay of Ten People
Loaves of Bread Sold
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1
2
3
4
5
6
7
7
189
34567789
00122345
014
1.
2
1 | 7 means 17
14b. mean: 39.5; median: 39.5; modes: 37, 40 and 42; range: 55
15. Dept. A: mean = 49.643, median = 50, mode = 58,
range = 31; Dept. B: mean = 51.857, median = 52,
mode = 52, range = 40 16. Locn. A: mean = 79.2,
median = 81, modes: 83 and 90, range = 24;
Locn. B: mean = 75.933, median = 75, mode = 66, range = 26
Reteaching 1-1
1. n + 5 2. n - 8 3. n
4. 5n - 3 5. 12n = 84
9
5 18
6. n - 7 = 22 7. 8x = 72 8. n
3
Reteaching 1-2
1. Check students’ work. 2. Check students’ work.
3. Check students’ work. 4. Check students’ work.
5. -3 6. -75 7. 2 8. 28 9. 3 10. -1
11. -20 12. -56
© Pearson Education, Inc., publishing as Pearson Prentice Hall.
Reteaching 1-5
Reteaching 1-3
1. rational, real 2. rational, real 3. whole, integer, rational,
real 4. rational, real 5. irrational, real 6. integers, rational,
real 7. rational, real 8. natural, whole, integers, rational,
real 9. natural, whole, integers, rational, real 10. integers,
rational, real 11. rational, real 12. irrational, real
13.–18. Check students’ work.
Reteaching 1-4
1. 60; 0; 60; s = 60b 2. 10; 5; 10; 5; c = 10h + 5
10
8
6
4
2
0
2.
2
6
8
4
U.S. Open Wins
10
2
6
8
4
Wimbledon Wins
10
10
Australian Open Wins
14a.
(continued)
French Open Wins
Chapter 1 Answers
8
6
4
2
0
3. no correlation 4. positive correlation
Reteaching 1-6
1. $915.60; $900; no mode 2. 5.375; 5; no mode 3. 12; 9; no
mode 4. 73.5; 73; 72 5. 70; 70; 70
Enrichment 1-1
1. O = 2I + 1 2. O = 3I - 1 3. O 5 I 2 2 1
4. S = 16T2 5. R 5 43 T 1 7 6. P = 2E + 1
7. Check students’ work.
Enrichment 1-2
Answers may vary. Samples include:
1. 3 3 2 3 2 2. "(8 1 8) 3. 23 4. (3 + 7) 3 4
5. (3 + 6) 3 6. 30 6 3 5 7. (3 3 9) - 2 8. 4 1 32
9. (10 2) + (3 3 3) 10. "25 3 3 2 2 2 1
11. (5 + 3 - 4) 3 3 12. 3 3 (8 - 2)
13. (4 3 4) + (2 3 4) - 6
Algebra 1 Chapter 1
Answers
33
(continued)
Enrichment 1-3
Chapter Project
Check students’ work.
Activity 1: Researching
Check students’ work.
1. The graph of the relation includes the line y = x. 2. It is
the empty relation (no ordered pairs). 3. equivalence relation
4. reflexive, transitive 5. asymmetric, transitive 6. none
7. symmetric, transitive 8. transitive 9. symmetric
10. symmetric 11. reflexive 12. symmetric 13. symmetric,
transitive 14. symmetric 15. asymmetric, transitive
Enrichment 1-5
1. Answers may vary slightly. 800 cc: $8000, fairly confident
1100 cc: $12,000, somewhat confident; 1350 cc: $14,000, not
very confident. 2. You could draw two trend lines, one running near the upper edge of the pattern and the other near the
lower edge. This would mark off a range of likely prices for
any given engine size. 3. Answers will vary. Possible answer:
Gathering data on larger-engine motorcycles, for instance up
to 1500 cc, would improve the basis for predictions in that
range. The data might also be reviewed to see whether selected data points can be discarded to obtain a pattern with better
correlation. For instance, one could discard data for a motorcycle brand known to be exceptionally expensive.
4. Answers may vary. Possible answer: The scatter plot might
look like this:
Activity 2: Modeling
In Geraldo’s equation, x represents the amount of money
he should save per week. The expression 40 + 16x represents
the total savings over 4 months, or 16 weeks, given that he
has already saved $40. Since Geraldo wants to determine
how much to save each month so that his total savings over
16 weeks is $129, he should solve 40 + 16x = 129 for x ;
check students’ work.
Activity 3: Organizing
Check students’ work.
Activity 4: Graphing
Check students’ work.
✔ Checkpoint Quiz 1
1. 14 + x; 18 2. 5z; 60 3. x + y; 7 4. 24
x ;6
5. 4z; 48 6. (y + z) + 10; 25 7. y + 2x; 11 8. xz; 48
9. false; Answers may vary. Sample: The opposite of -2 is -2,
which is not a positive number. 10. false; Answers may vary.
Sample: -5°F is a reasonable temperature but is not a whole
number.
✔ Checkpoint Quiz 2
1. c = 5+ 0.5g 2. negative correlation 3. mean: 16;
median: 16; mode: 17; mean and median 4. mean: 2;
median: 2; mode: 1; mean and median 5. mean: 29;
median: 27.5; mode: 25; median
Chapter Test, Form A
Weather tends to be more variable at high elevations
than at low ones, and more variable weather would involve
greater variations in temperature.
1. s = 150m 2. r = 100 - t 3. 20 4. 77 5. 5 6. 21
7. 29 8. 16 9. 20 10. 9.4 11. 4 12. 3
5
13. -5.1, 5.001, 5.01, 5.1 14. 21 , 23 , 1 , 2
2
Enrichment 1-6
1. mode; by the phrase “most frequent” 2. Check students’
work. 3. 34.25 mi/gal, 35 mi/gal, 41 mi/gal; The mean and
median are close, but the mode is much higher. 4. Answers
may vary. Sample: Not very reliable. Only 25% of the cars
tested got 41 mi/gal or better. 5. Answers may vary. Sample:
75% of Worldwide Motors’ cars tested at less than 40 mi/gal.
8 5 3
15. false; " 2 is a real number that is not rational.
1 1 19. independent
16. true 17. 4 - (x + 6) 18. n
2
variable: number of teachers; dependent variable: number of
students; s = 30t 20. independent variable: number of long
distance minutes; dependent variable: cost; c = 0.10m + 15
21. time of day; air temperature 22. height; reach
23. memory; speed 24. mean: 6.2; median: 6.2; mode: 6.2; all
25. mean: 48.6; mode: 47; median: 47; mode and median
26. 13 27. 6.3 28.
29. positive
1 26
2 49
3 278
4 1
5 9
30. 65 in. 31. 0.23 is greater than 29 since 29 5 0.22 and
0.23 . 0.22
34
Answers
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Enrichment 1-4
Algebra 1 Chapter 1
© Pearson Education, Inc., publishing as Pearson Prentice Hall.
Chapter 1 Answers
Chapter 1 Answers
(continued)
Chapter Test, Form B
1. c = 3n 2. r = 162 - p 3. 8 4. 1 5. 16 6. 36
7. 0 8. 49 9. 27 10. 51.4 11. true 12. false; Answers may
vary. Sample: The opposite of ∆7« is -7, which is not positive.
TASK 3 Scoring Guide:
a. Check students’ work.
b. A = 5h
Domain: 0 to 6 hours
Range: $0 to $30
13. 4m 14. x + 5x
All rights reserved.
15. independent variable: number of hours; dependent
variable: number of dollars earned; d = 8h 16. mean: 5;
median: 5; mode 2; range: 9 17. mean: 31;
median: 34; mode: 35; range: 26 18. negative correlation
19. one h 20. 22 23 is less than -2.6 since 22 2 5 22.6
3
and 22.6 , 22.6 .
Alternative Assessment, Form C
TASK 1 Scoring Guide:
a. 8x 5 7 1 x
4
c. x2 + y = 42
3 Clear and coherent rules are given. Function rule is
correct, and domain and range are clearly described.
2 Rules are basically correct but are unclear or incomplete. Domain and range are not specific.
1 Student makes some attempt to answer prompts.
0 No attempt is made, or no solution is presented.
TASK 4 Scoring Guide:
3 The response is complete and demonstrates a clear
understanding of mean, median, and mode. Data are
correctly expressed as percents, with ten scores between
70% and 79%, ten scores in the combined ranges
80%–89% and 60%–69%, and five scores in the
combined ranges 0%–59% and 90%–100%. The mean,
median, and mode are correctly calculated on the basis
of the student’s data. An appropriate graph is chosen to
display the data.
b. 5x - 8 = 32
d. 1 x 1 x 5 3(x 2 7)
3
3 Shows a clear understanding of the concepts of translating words to mathematical equations and can identify
the key words or phrases. The sentences are all written
correctly.
2 The answer is mostly correct. Data are correctly chosen,
but there are slight errors in calculations. Explanations
are clear.
2 Translations are given for each of the exercises with
© Pearson Education, Inc., publishing as Pearson Prentice Hall.
minor errors.
1 Student makes some attempt to write the translations.
1 Data do not fit the distribution correctly. There are
serious errors in calculations, or explanations are
unclear or incorrect.
The equations are translated incorrectly.
0 No attempt is made, or no solution is presented.
0 Student makes no attempt, or no solution is presented.
TASK 2 Scoring Guide:
a. 26
Cumulative Review
b. In either case, the same order of operations must
1. A 2. G 3. A 4. F 5. B 6. H 7. C 8. H 9. A 10. H
11. D 12. H 13. 9 14. 71 15. 31 16. c = 1.5n
17. r = 8 - w 18. mean: 2.1; median: 2; modes: 1 and 2;
median 19. mean: 14; median: 13; mode: 13; median, mode
20. Answers may vary. Sample: 30, 17, 80, 15, 8; To find the
be followed.
c. Check students’ work.
3 Both expressions are correctly simplified. Each step is
clearly identified and explained. The steps are compared,
and explanations show a thorough understanding of
grouping symbols, exponents, and order of operations. A
new expression is presented and simplified correctly.
2 The answer is mostly correct, but some steps are omit-
average of the five numbers, add them and divide by 5.
21.
5
6
7
8
9
26
01158
134
ted. A clear explanation is given, but it shows a lesser
degree of insight.
1 The response is partially satisfactory, but major steps are
omitted. Explanations are incomplete or unclear.
0 No attempt is made, or no solution is presented.
Algebra 1 Chapter 1
Answers
35
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