Name: Date: Lesson 2.5 Operations with Rational Numbers
Evaluate each expression. Give your answer in simplest form.
8
3
1. 

1
2. 4  7 
4
 9
15
 1
5
3. 7 4 4.  
 3
8
15
5
5.
 5
 2
2
1
2 2  6. 2  2 
 9
 3 
3
6
21
3
7. 2 1 2 2 8.
2
7
15
14
9.
 1
23
2 2   2
4
 23  5
2
10. 2 2   2
 4  8
5
11.
 2 3
1
2 2  2  5 4
3
12.
 21  23 
22
2   2  
3  5 
9
14.
 5   1
4
   
 6  3
9
 3  5
5
13. 2    4  8
6
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5
20 Chapter 2 Lesson 2.5
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Name: Date: Evaluate each product. Give your answer in simplest form.
15. 3 5 4
17. 12
14  3 
1  25  7 
19. 2 2 3 3  3 
4
16. 2 1 8
4
18. 1
20.
27
8 
2
2 
27 
5
2  2
1 
15  3 
Evaluate each quotient. Give your answer in simplest form.
1
4
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21. 3
8
22.
 4
2
 
 35 
5
 5
1
23.    18 
6

2
1
24. 1 3 
 3
3
 3  3
25. 2  1   4  8
26.
2
27. 3 216
29.
 4
2 
 5
 7
2 
 20 
28.
30.
210
5
13
7
8
 3
2 
 4
 2
22 
 5
1
1
5
Extra Practice Course 2A 21
MIF_ExtraPractice C2_Ch02.indd 21
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Name: Date: Solve. Show your work.
31. A restaurant used 8 5 pounds of rice on Monday and 5 1 pounds of rice on
6
6
Tuesday. How many more pounds of rice did the restaurant use on Monday
than on Tuesday?
32. Janet has 9
1
2
feet of material. She needs to cut lengths of
feet.
3
3
How many complete lengths can she cut?
33. A recipe calls for 2 1 cups of walnuts. Only 5 cup of walnuts are on hand.
6
2
How many more cups of walnuts does he need for the recipe?
34. The sum of two rational numbers is 28 1 . If one of the numbers is 25 2 ,
4
3
35. Parcel P weighs 4 1 pounds, parcel Q weighs 3 2 pounds and parcel R
weighs 6
5
2
4
pounds. Find the average weight of the three parcels.
5
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find the other number.
22 Chapter 2 Lesson 2.5
MIF_ExtraPractice C2_Ch02.indd 22
08/12/11 2:58 PM
16.480  (6 1 14) 2 7(4) 1 8(3 1 4)
5 480  (20) 2 7(4) 1 8(7)
5 480  (20) 2 28 1 56
5 24 2 28 1 56
5 24 1 56
5 52
17. Area remained:
Total area of the rectangle 2 area of the cut
out triangles 2 area of the cut out rectangles
5 12  8 2 2 
1
442243
2
5 96 2 16 2 24
5 56 in2
The area of the remaining paper is 56 in2.
18. Volume of water pumped out for 3 days
5 3  210
5 630 gal
Water volume 3 days ago 5 6,600 1 630
5 7,230 gal
Lesson 2.5
8
3
1. 2.
1
8 4
1 3
4
3 4
43
32
3
12
12
32 3
12
29
12
5
2
12
 7
4
4
7
  15  9 
15
9
43
7 5
15 3
95
12
35
45
45
12 35
45
23
45
7
4
7 1 4 3
3. 15
5
15 1
53
7 12
15
15
7 12
15
5
15
1
3
© Marshall Cavendish International (Singapore) Private Limited.
5. 248  4(25) 2 17
5 248  (220) 2 17
5 2.4 2 17
5 214.6
6. 235 2 490  7 1 12
5 235 2 70 1 12
5 2105 1 12
5 293
7.82 2 (9 2 13)(9)
5 82 2 (24)(9)
5 82 1 36
5 118
8. 227 2 (4 1 4)(3)
5 227 2 (8)(3)
5 227 2 24
5 251
9.90  (26 2 3) 1 45
5 90  (29) 1 45
5 210 1 45
5 35
10.(16 1 2)(3) 2 5(25 1 3)
5 (18)(3) 2 5(22)
5 54 2 (210)
5 54 1 10
5 64
11. 230 1 5(3 1 8) 2 45
5 230 1 5(11) 2 45
5 230 1 55 2 45
5 275 1 55
5 220
12.25  [24 1 (21)] 2 9(3)
5 25  (25) 2 9(3)
5 25  (25) 2 27
5 25 2 27
5 232
13.36  6 2 (225 1 15)(4)
5 36  6 2 (210)(4)
5 36  6 2 (240)
5 6 2 (240)
5 6 1 40
5 46
14. 242 1 70  (22 2 3) 1 84  (4 1 2)
5 242 1 70  (25) 1 84  6
5 242 2 14 1 14
5 256 1 14
5 242
15. 2200 1 32  (23 1 7) 2 45(15 2 20)
5 2200 1 32  4 2 45(25)
5 2200 1 128 1 225
5 272 1 225
5 153
92 Answers
MIF_ExtraPractice_C2_Ch01-Ch05_Ans_86-129.indd 92
09/12/11 1:45 AM
4.
5  1 
5
1
   3
8
8
3
1 8
5 3
83
38
15
8
24
24
15 8
24
23
24


9. 3  1  3 1 1 2
 2
4
4 1 2 2
3
2
4
4
3 2
4
1
4
5.
2  5
2
5
  3  9
3
9
23
5 1
33
9 1
6
5
9
9
65
9
11
9
2
1
9
 
10. 2  3  5 2 3 5
5  4  8
5
4
8
28
3 10
55
58
4 10
85
16
30
25
40
40
40
16 30 25
40
11
1
40
6.
11.
1 20
2 12
3 15
3 20
5 12
4 15
20
24
45
60
60
60
20 + 24 − 45
60
1
60
1  2 
1 2
  6  3 
6
3
1 1 2 2
6 1 3 2
1
4
6
6
1 4
6
5
6
1
2
1 3
2 1
7. 5
15
53
15 1
3
2
15
15
3 2
15
5
15
1
3
1
3
1 2
3 1
8.
7
14
7 2
14 1
2
3
14
14
2 3
14
5
14
© Marshall Cavendish International (Singapore) Private Limited.
1  2 3
1 2
3
  3  5 4
3
5
4
12.
2  1  3 
2
1 3
   3  5 
9
9
3
5
2 5
1 15
39
95
3 15
59
10
15
27
45
45
45
10 15 27
45
32
45
5  3 
5
5
3
5
13.   6
4
8
6
4
8
5 4
36
53
64
46
83
20
18
15
24
24
24
20 18 15
24
23
24
Extra Practice Course 2A 93
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09/12/11 1:45 AM
4  5   1
4
5
1
    6  3
9
9
6
3
42
53
1 6
92
63
36
8
15
6
18
18
18
8 15 6
18
29
18
11
1
18
1
4
21. 3
1 8
8
4 3
3
4
15. 3 5
5
12
4 12 4
1
1
14 
3
14
10
1   
25 
7
25  7 
14 10
7
35 12
2
8 15
1
2  2
2  5
1   
20.
15  3 
15  3 
2 5
3
5
3 41
10
1
15 3
6 5
5 3
1
3 10 2
1
2
 3   3   11  11
25. 2  1     
 4  8  4   8 
11  8 
.  
4  11
4
28
9
1
3
9
2
3
8
15
19. 2  3   
3 
4
3  4
1
27 5 1
3
3
5
1
4
5
9
1 18
1
2
8 
2
35  12 
2   
27 
5
27  5 
7
2
2 
1
5  10 
24. 1 3   


3
3
3  3
25 7 1
5
5 42
1
2
3
7
1
2
1  5
1  18 
23.    
6  18 
6  5
2
2
2 35
1
9 8
1 4 27 3
18. 1
2
3


2
4
22.   2  35  5  35 
5  4
3
5
16
1 8
9 8
16. 2 4 27
4 27
2
4 3
1
1
17. 1 8
1
2
10
5
26.
10 5
13
13
2
10 13
1
51
26
2
27. 3 2 (16)
3
16
1
2
1
3 16 8
11 8
2
4 111
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14.
1
24
2
9
94 Answers
MIF_ExtraPractice_C2_Ch01-Ch05_Ans.indd 94
09/12/11 6:40 PM
33. Number of cups:
7
7  3
8
28.
 
8
4
 3
 4 
7 4
3
2 8
1
2
1
7
6
1
1
6
 4
 
29.  5  4  7 
5  20 
 7
 20 
4 20
7
15
4
34. The other number: 1 
2
33 17
8 5  
4
3
4
3
44
1 7
30.
2

 2 5 
1
1
5
12
6
5
5
12 5
5
6
2 12 5
1
1
2
© Marshall Cavendish International (Singapore) Private Limited.
1
53
31
6
6
6
53 31
6
22
6
2
3
3
2
2
3
2
5
4
5
The restaurant used 3 pounds more
3
rice on Monday than on Tuesday.
32. Number of lengths Janet can cut:
9 7
.
12
9
17
34
2
5
5
9 5 17 2
34 2
25
52
52
45
34
68
10
10
10
147
10
5 61
31. Amount of rice used on Monday 2
Amount of rice used on Tuesday:
5
6
The other number is 22
35. Total weight 4 3 6
1
2
8 5
33 3 17 4
43
3 4
99
68
12
12
31
12
7
2
12
16
7
2
2
7
5
5
5
6
2
6
53
5
23
6
15
5
6
6
15 5
6
10
6
2
1
3
2
The chef needs 1 cups of walnuts.
3
2 147
3
10
147 1
10 3
49
10
9
4
10
Average Weight 1
29 3
3
3 1
29
Janet can cut 29 complete lengths.
Extra Practice Course 2A 95
MIF_ExtraPractice_C2_Ch01-Ch05_Ans.indd 95
09/12/11 6:40 PM