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Name _______________________________________ Date __________________ Class __________________
LESSON
1-2
Review for Mastery
Adding and Subtracting Real Numbers
You can model integer addition using two-color counters. Use the yellow
side for 1 and the red side for 1. A yellow counter and a red counter are
opposites, so they sum to 0 and cancel.
Add 4  6.
4  6 
2
To subtract integers using counters, remember that subtracting a number
is the same as adding the opposite of the number.
Subtract 5  8.
To subtract 8, add 8.
5  8  5  (8) 
 3
Add or subtract by drawing a model of two-color counters.
1. 2  (5) 
2. 4  (1) 
_________________
_________________
Add or subtract using two color counters.
3. 3  7
________________________
6. 8  2
________________________
9. 6  (4)
________________________
4. 3  (4)
5. 2  6
________________________
7. 5  3
________________________
8. 7  (4)
________________________
10. 5  (5)
________________________
11. 2  7
________________________
________________________
Original content Copyright © by Holt McDougal. Additions and changes to the original content are the responsibility of the instructor.
1-14
Holt McDougal Algebra 1
Name _______________________________________ Date __________________ Class __________________
Review for Mastery
LESSON
1-2
Adding and Subtracting Real Numbers continued
These rules apply to the addition of all real numbers, not just integers:
To Add Numbers with the Same Sign
Add the numbers’ absolute values and use the same sign as the numbers.
To Add Numbers with Different Signs
Find the difference of the numbers’ absolute values and use the sign of the
number with the greater absolute value.
Add 
 3
1
   .
5
 5
Use the rule for adding numbers with the same sign.

1
1

5
5

and
3
3

5
5
1
3
4


5
5
5
Find the absolute values.
Add the absolute values.
Use the same sign as the numbers.

 3
1
4
    
5
5
 5
Both addends are negative, so the result is negative.
Subtract 2.9  (3.5).
Change subtraction to addition.
To subtract 3.5, add 3.5.
2.9  3.5
Use the rule for adding numbers with different signs.
2.9  2.9 and
3.5  3.5
3.5  2.9  0.6
Find the absolute values.
Find the difference.
Use the sign of the number with the greater absolute value.
2.9  (3.5)  0.6
3.5 had the greater absolute value in the addition
problem, so the result is positive.
Add or subtract.
12. 5  (9)
________________________
15. 12  (15)
________________________
13. 6.5  (3.2)
14. 
________________________
16. 7.8  2.5
________________________
5
1

9
9
________________________
17.
3
5

8
8
________________________
Original content Copyright © by Holt McDougal. Additions and changes to the original content are the responsibility of the instructor.
1-15
Holt McDougal Algebra 1
4.Possible answer: It depends on the
number of minutes used. Plan A is
cheaper if you use less than 300
minutes each month. Plan B is cheaper
if you use more than 300 minutes each
month. If you use exactly 300 minutes
each month, the plans cost the same.
Problem Solving
1. 45d
14. 28
15. 2.4
16. 6
17. 37
18. 2.5
19. 116°F
20. $6.26
21. 31
22. 9.45
1
5
1. 4
2. 11
3. 12
4. 42
5. 1.6
6. 2
6. F
7. B
Reading Strategies
7. 
1. Possible answers: 10y, 10 • y, and
10(y)
13. 
6. 58  t
Practice A
2. 6
3. 0
4. 3
5. 7
6. 18
7. 2
8. 4.2
9. 5
10. 29
11. 7
12. 22
13. 5
14. 7
15. 15
16. 11
17. 16 feet
18. 3 points
5
6
11. 15.1
4. 4  b
1. 6
1
30
9. 4
2. Possible answers: k divided by 6, the
quotient of k and 6
5. 20m
LESSON 1–2
13. 45
Practice C
550
4.
; $22, $11, $10
p
3. b  4
12. 12.4
23. 2
2. 5.15  w
3. 216  t
5. C
11. 2
5
6
1
5
8. 0.3
10. 22
12. 3
14. 3
15. 9.5
16. 7 feet
17. $24,577
18. 31
19. 1.75
20. 2
2
3
Review for Mastery
1. 3
1
2
2. 5
Practice B
3. 4
4. 1
1. 14
2. 10
5. 8
6. 6
3. 6
4. 4
7. 8
8. 11
5. 0
6. 4.25
9. 2
10. 0
7. 18
8. 24
11. 5
12. 4
13. 9.7
14.
9. 20.9
10. 4
2
5
5
8
4
9
Original content Copyright © by Holt McDougal. Additions and changes to the original content are the responsibility of the instructor.
A2
Holt McDougal Algebra 1
16. 10.3
15.3
17. 
2
1

8
4
Challenge
5. 8
6. 6
7. 14.31
8. 63
9. 2
10. 5
11. 3
12. 3
13. 
2
3
14. 
Math Expression
Balance
$450  ($25)
$425
$425  ($200)
$225
$225  $50
$275
$275  $50
$325
21.
1
2
22. 2
$325  ($350)
$25
23. 0
24. 0
$25  $75
$50
25. undefined
$50  ($25)
$25
$25  $100
$125
$125  ($200)
$75
$75  $225
$150
15. 3
16. undefined
17. 1
18. 0
19. 10 points
20. 72
Practice B
1. no
2. yes; 3/23 and 5/17
3. $150
4. yes
1. 3
2. 120
3. 32
4. 120
5. 105
6. 4
7. 
1
4
 1
3
3
9. 
27
64
Problem Solving
1. 1195 feet
inches
2. 68 feet 6
3. 44.18 points
4. 10 points lower
5. A
6. F
Reading Strategies
1. negative
2. because subtraction problems become
addition problems
4. 30
5. 3
6. 11
7. 9
8. 19
8. 50
10. 0
11. 0
12. undefined
13. $1250
14. 0.54
15. 1
16.
17. 
7. D
3. 13
1
16
1
4
5
1
2
2
2
18. 64
1
2
19. 32
20.
21. 8
22. 2
23. 8
24. 4
25. 
1
8
Practice C
LESSON 1–3
1. 120
2. 2
Practice A
3. undefined
4.
1. 24
2. 20
3. 0
4. 
5. 
3
8
7
36
1
15
6. 7
7.
28 8.
0
Original content Copyright © by Holt McDougal. Additions and changes to the original content are the responsibility of the instructor.
A3
Holt McDougal Algebra 1