Name______Date______
Estimating Decimal Quotients 5NBT.7
Complete with the teacher.
1)Which of the following will provide the closest estimate for 3.13 X 49.72?
A)3 X 40 = 120
B)4 X 40 = 160
C)4 X 50 = 200
D)3 X 50 = 150
2)Raul rounded 2.95 to 3 and 11.7 to 12. He then used mental math to do
3 X 12 = 36. Is his estimateanoverestimate or an underestimate and why? ______
3)You are shopping in a video game store. Video games are on sale for $7.62 each,
including tax. About how much will 5 video games cost? Explain how you estimated to get you answer.
______
4)Yvonne multiplied 2.5 and 60.7 to find the product. Use estimation to determine which of the following answers is reasonable.
A) 1,517.5
B) 151.75
C) 15.175
D) 1.5175
Explain why you chose this answer.
______
Complete with a partner.
1)Which of the following will provide the closest estimate for 789.34 X 41.5?
A) 800 X 40 = 32,000
B) 700 X 40 = 28,000
C) 700 X 50 = 35,000
D) 800 X 50 = 40,000
2)Henry rounded 519.56 to 500 and 33.4 to 30. He then used mental math to do 500 X 30 = 15,000. Is his estimateanoverestimate or an underestimate and why? ______
3) Jessica is on a swim team and swims laps practicing different strokes. She practiced for 48 days. Each day she swam 53.2 laps. Estimate the number of laps Jessica swam in all. Explain how you estimated to get you answer.
______
4)Joe multiplied 67.4 and 21.8 to find the product. Use estimation to determine which of the following answers is reasonable.
A) 14,693.2
B) 1.46932
C) 146.932
D) 1,469.32
Explain why you chose this answer.
______
Complete independently.
1)Which of the following will provide the closest estimate for 38.73 X 17.40?
A) 40 X 20 = 800
B) 30 X 20 = 600
C) 40 X 10 = 400
D) 30 X 10 = 300
2)Jackie rounded 66.37 to 70 and 8.88 to 9. He then used mental math to do
70 X 9 = 630. Is herestimateanoverestimate or an underestimate and why? ______
3)The Robinson family went on a trip to Colorado. Each day they drove 582.7 miles. They drove for 4 days. Estimate the total number of miles the Robinson’s drove in the 4 days. Explain how you estimated to get you answer.
______
4)Beth multiplied 12.1 and 4.82 to find the product. Use estimation to determine which of the following answers is reasonable.
A) 583.22
B) 5.8322
C) 58.322
D) 5,832.2
Explain why you chose this answer?
______
Answer Key
Complete with the teacher.
- D
- overestimate
- Sample response: 3 is a little more than 2.95 and 12 is a little more than 11.7 so the estimate would be a little more than the exact answer.
- Answers may vary.
- Possible solution: It will cost about $40 because each game is about $8 and 8 X 5 = 40
- B
- Sample response: I used these numbers to estimate 3 X 60 = 180 and I chose the number that was closest to this.
Complete with a partner.
- A
- Underestimate
- Sample response: 500 is a little less than 519.56 and 30 is a little less than 33.4 so the estimate would be a little less than the exact answer.
- Answers may vary.
- Possible solution: She practiced for about 50 days and she swam about 50 laps each day. So, she swam about 2,500 laps.
- A
- Sample response: I used these numbers to estimate 70 X 20 = 1,400 and I chose the number that was closest to this.
Complete independently.
- A
- Overestimate
- Sample response: 70is a little more than 66.37 and 9 is a little more than 8.88 so the estimate would be a little more than the exact answer.
- Answers may vary.
- Possible solution: They traveled about 2,400 miles because 582.7 is about 600 miles and they traveled for 4 days. So, 600 X 4 = 2,400
- C
- Sample response: I used these numbers to estimate 12 X 5 = 60 and I chose the number that was closest to this.