Decimal Computation Chapter Questions
1. Explain how to complete long division
2. What are the steps for adding decimals?
3. What are the steps for subtracting decimals?
4. What happens when you divide decimals?
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Chapter Problems
Long Division
Classwork
Complete the following computations.
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
11) Bryan bought 4 bags of peanuts from the grocery store. Each bag of has the
same number of peanuts. If Bryan bought a total of 564 peanuts, how many
peanuts come in each bag?
12) Clara slept for a total of 126 hours over the course of two weeks. If she sleeps for
the same amount of time each night, how many hours does she sleep per night?
Homework
Complete the following computations.
13)
14)
15)
16)
17)
18)
19)
20)
21)
22)
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23) Delia had several packages of jellybeans. She opened them all and had 684
jellybeans. If each package has 76 jellybeans, how many packages of jellybeans
did she open?
24) Max rides his bike the same distance every day. Over the course of three weeks,
he biked 84 miles. How many miles did he bike each day?
Adding Decimals
Classwork
Complete the following computations.
25) 162.4221 + 198.3
26) 128.272 + 171.35
27) 100.67 + 157.9094
28) 89.5231 + 83
29) 136.742 + 182.3
30) 30.765 + 32.42 + 12.1
31) 142.2 + 106.066 + 98
32) 118.36 + 60.8897 + 3.8
33) 103.924 + 181.9 + 14.3 + 145.32
34) 34.281 + 60.1702 + 12.89 + 45
35) Sandra loves red licorice rope. She has one piece that is 175.3 cm long, another
that is 71.23 cm, and a third that is 101.333 cm long. How much licorice does she
have all together?
36) A recipe calls for 0.55 mL of vanilla extract, 1.05 mL of almond extract, and 0.75
mL of mint extract. How much extract does the recipe require?
Homework
Complete the following computations.
37) 184.77 + 20.98
38) 52.8 + 159.519
39) 120.846 + 138.4676
40) 200.1 + 24.94
41) 194.032 + 72.1
42) 35.68 + 85.8894 + 16.89
43) 116.492 + 82.514 + 49.32
44) 87.648 + 186.1 + 95.6
45) 64.4591 + 76.9125 + 15.889 + 83
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46) 100.44 + 15.64 + 98.723 + 109
47) Charles and his friends are building a model train track. Charles has 12.5 m of
railway track. His friend Michael has 8.6 m, and his friend Kristy has 4.8 m. When
they put their track together what will the total length be?
48) For Mother’s Day, Sophia buys her mom a bunch of flowers for $12.95, and box
of chocolates for $3.95, and a card for $1.78. How much did she spend?
Subtracting Decimals
Classwork
Complete the following computations.
49) 15 – 0.12
50) 4.71 - 3
51) 13 – 6.62
52) 232.157 – 55.288
53) 226.126 – 78.6
54) 686.41 – 9.256
55) 98.111 – 78.093
56) 915.469 – 42.7
57) 796.324 – 39.85
58) 306.935 – 89.967
59) If your weekly salary is $520, how much do you take home each week after
deductions are made for taxes of $82.14, $9.77, $31.35 and $41.25?
60) Franklin spent $37.46 at the grocery store. The cashier gave him $2.54 in
change from a $50 bill. What did the cashier do wrong?
61) Tara wanted to buy a DVD player for $49.95, a DVD case for $19.95 and a BluRay player for $149.99. Does she have enough money to buy all three items if
she has $215 with her?
Homework
Complete the following computations.
62) 12 – 1.77
63) 18.62 - 9
64) 17 – 5.91
65) 700.746 – 60.122
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66) 716.835 – 37.43
67) 675.66 – 11.44
68) 698.54 – 7.652
69) 286.583 – 280.789
70) 457.4 – 2.609
71) 521.549 – 0.772
72) If your monthly salary is $1600, how much do you take home each week after
deductions are made for taxes of $324.58, $43.15, $126.75 and $207.54?
73) Sam spent $76.56 at the electronics store. The cashier gave him $33.44 in
change from a $100 bill. What did the cashier do wrong?
74) Tom wanted to buy a stereo for $159.95 and 2 DVDs for $19.95 each. Does he
have enough money to buy all three items if he has $200 with him?
Multiplying Decimals
Classwork
Complete the following computations.
75) 366 x 0.53
76) 4.09 x 0.88
77) 9.7 x 0.69
78) 4.6 x 0.36
79) 0.42 x 0.43
80) 3.407 x 4.9
81) 43.8 x 0.56
82) 5.09 x 0.57
83) 7.28 x 0.002
84) 70.15 x 0.0029
85) If peanuts cost $6.59 a pound, how much would it cost to buy three and a half
pounds of peanuts?
86) You need to buy 7 notebooks that cost $0.74 each. How much will this cost?
Homework
Complete the following computations.
87) 0.05 x 0.4
88) 9.681 x 0.46
89) 0.51 x 0.13
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90) 39.3 x 0.26
91) 8.36 x 4.4
92) 1.575 x 0.005
93) 285.6 x 0.29
94) 0.001 x 0.223
95) 657.8 x 0.44
96) 3961.2 x 0.012
97) If candy cost $5.99 a pound, how much would it cost to buy four and a quarter
pounds of candy?
98) You need to buy 5 books that cost $12.99 each. How much will this cost?
Dividing Decimals
Classwork
Complete the following computations.
99) 272.7 ÷ 2.25
100) 382.3 ÷ 0.5
101) 540.9 ÷ 3
102) 534.27 ÷ 10
103) 770.553 ÷ 567
104) 3.86 ÷ 0.18
105) 38.24 ÷ 0.15
106) 34.04 ÷ 4.4
107) 0.6 ÷ 0.9
108) 96.86 ÷ 0.44
109) How much gas can you buy with $20 if it costs $2.39 per gallon?
110) Jen studied for 16.1 hours over a period of 3.5 days. On average, how much
did she study each day?
Homework
Complete the following computations.
111) 364.26 ÷ 0.52
112) 780.485 ÷ 0.1
113) 21.7 ÷ 70
114) 5.36 ÷ 53.6
115) 188.32 ÷ 0.4
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116) 60.7 ÷ 1.8
117) 0.7 ÷ 0.6
118) 61.3 ÷ 0.37
119) 6.94 ÷ 0.3
120) 98.43 ÷ 0.37
121) Paint costs $24.99 a gallon. How much paint can he buy if he has $90, how
many gallons can he buy?
122) How much gas can you buy with $30 if it costs $2.33 per gallon?
Unit Review
Decimal Computation Multiple Choice Questions
123)
124)
125)
35.938 + 543.5
126)
75 – 8.47
a. 413.73
a. 7.72
b. 41.373
b. 66.53
c. 578.438
c. 77.2
d. 579.438
d. 665.3
96.3 + 2.576 + 154.2 + 50
127)
751.42 – 367.9
a. 513.1
a. 7147
b. 303.076
b. 714.7
c. 558.1
c. 383.52
d. 303.13
d. 38.352
86.542 + 67
128)
266.37 – 215.38
a. 153.542
a. 50.99
b. 1535.420
b. 51.01
c. 932.42
c. 51.19
d. 866.09
d. 50.19
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129)
130)
131)
4.25 x 0.96
133)
a. 408
a. 63.2
b. 40.8
b. 0.632
c. 40800
c. 6320
d. 4.08
d. 6.32
535 x 9.84
134)
3.0976
a. 5.2644
a. 0.352
b. 52.644
b. 35.2
c. 5264.4
c. 352
d. 526.44
d. 3.52
72.3 x 0.0058
135)
a. 0.41934
0.88
2.2
b. 3.6354
c. 4.1934
c. 36.354
d. 419.34
2469.6
79.98
80
a. 363.54
b. 41.934
132)
5056
d. 3635.4
84
a. 29.40
b. 2940
c. 2.940
d. 294.0
Decimal Computation Short Constructed Response Questions
136)
187.6 + 39.35 + 5.732 =
______________
137)
879.257 – 29.39 =
______________
138)
434.7 x 0.009 =
______________
139)
61.215
______________
140)
635.8
0.07 =
0.99 =
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Decimal Computation Extended Constructed Response Questions
141)
Stephanie purchased a sweater for $57.98, including tax. She gave the
cashier one $20 bill, three $10 bills, one $5 bill, six quarters, eleven dimes, and
eight nickels.
a. How much money did Stephanie give to the cashier?
b. How much change will Stephanie receive from the cashier?
c. Show all of your work to support your answers.
142)
Kyle is mailing three packages to a friend. The packages weigh 3.4
pounds, 8.6 pounds, and 14 pounds. Postage will cost $1.35 per pound.
a. Find the total weight of the three packages.
b. Find the total cost of mailing all three packages.
c. Show all of your work to support your answers.
143)
Sean wants to find a summer job. He was offered a job at a local
restaurant where he will make $150 per week. He was also offered a job working
for a landscaping company for $7.50 per hour for 8 hours per day, three days per
week.
a. Determine the amount Sean will make per week at each job.
b. Describe which place Sean should choose to work and explain why.
c. Show all of your work to support your answers.
144)
Melanie went away on vacation and wanted to send some postcards and
letters to her family about her trip. Postcards cost $0.45 to buy and send and
letters cost $1.35 to buy and send. Melanie spent $6.30 on the letters and
postcards that she sent.
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a. Determine the number of postcards Melanie sent.
b. Determine the number of letters Melanie sent.
c. Show all of your work to support your answers.
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Answer Key
1) 12
24) 4 miles per day
2) 92
25) 360.7221
3) 19
26) 299.622
4) 44
27) 258.5794
5) 54
28) 172.5231
6) 195.8
29) 319.042
7) 236.5
30) 75.285
8) 89.3
31) 346.266
9) 214.5
32) 183.0497
10) 212.48
33) 445.444
11) 141 peanuts per bag
34) 152.3412
12) 9 hours per night
35) 347.863 cm
13) 56
36) 2.35 ml
14) 14
37) 205.75
15) 34
38) 212.319
16) 56
39) 259.3136
17) 98
40) 225.04
18) 91.9
41) 266.132
19) 99.3
42) 138.4594
20) 90.8
43) 248.326
21) 219.78
44) 369.348
22) 88.55
45) 240.2606
23) 9 packages
46) 323.803
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47) 25.9 m
68) 690.888
48) $18.68
69) 5.794
49) 14.88
70) 454.791
50) 1.71
71) 520.777
51) 6.38
72) $897.98
52) 176.869
53) 147.526
73) The correct change was $23.44.
The cashier gave him $10 too
much.
54) 677.154
74) Yes (it will cost $199.85)
55) 20.018
75) 193.98
56) 872.769
76) 3.5992
57) 756.474
77) 6.693
58) 216.968
78) 1.656
59) $355.49
79) 0.1806
60) The correct change was $12.54.
The cashier gave him $10 less
than he should have.
80) 16.6943
61) No (it will cost $219.89)
82) 2.9013
62) 10.23
83) 0.01456
63) 9.62
84) 0.203435
64) 11.09
85) $23.07 (rounded)
65) 640.624
86) $5.18
66) 679.405
87) 0.02
67) 664.22
88) 4.45326
89) 0.0663
90) 10.218
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91) 36.784
107)
92) 0.007875
108)
93) 82.824
109) 8.37 gallons
94) 0.000223
110) 4.6 hours p/day
95) 289.432
111)
700.5
96) 47.5344
112)
7804.85
97) $25.46
113)
0.31
98) $64.95
114)
0.1
99) 121.2
115)
470.8
100)
764.6
116)
101)
180.3
117)
102)
53.427
118)
103)
1.359
119)
104)
120)
105)
121) $112.46
106)
122) 12.88 gallons
Decimal Computation Multiple Choice Questions Answer Key
123)
d
128)
a
133)
a
124)
b
129)
d
134)
d
125)
a
130)
c
135)
c
126)
b
131)
a
127)
c
132)
a
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Decimal Computation Short Constructed Response Questions Answer Key
136)
232.682
139)
874.5
137)
849.867
140)
642.2
138)
3.9123
Decimal Computation Extended Constructed Response Questions Answer Key
$20 + 3 x $10 + $5 + 6 x $0.25 + 11 x $0.10 + 8 x $0.05 = $58 was given to the
cashier.
141.
b. $58.00- $57.98 = $0.02 Stephanie should receive $0.02 in change from the
cashier.
142.
a. 3.4 + 8.6 + 14 = 26 pounds
b. 26 x $1.35 = $35.10
143.
$150 at the restaurant, $7.50 x 8 x 3 = $180 at the landscaping company
b. Sean should work at the landscaping company because he makes $30 more
per week there than at the restaurant.
144.
a. 5 x $0.45= $2.25, 5 postcards
b. 3 x $1.35 = $4.05, 3 letters; $2.25 + $4.05 = $6.30
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