5th Grade Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 5th Grade place value worksheet.
Success TutoringWorksheetsAnswer sheet5th Grade · Mathematics · Place Value5th Grade Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 3 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 71 + 21 by rounding each number to the nearest 10.
Answer: 90
- 71 rounds to 70; 21 rounds to 20
- 70 + 20 = 90
The exact answer is 92, close to the estimate.
2.Estimate 72 + 79 by rounding each number to the nearest 10.
Answer: 150
- 72 rounds to 70; 79 rounds to 80
- 70 + 80 = 150
The exact answer is 151, close to the estimate.
3.Estimate 59 − 41 by rounding each number to the nearest 10.
Answer: 20
- 59 rounds to 60; 41 rounds to 40
- 60 − 40 = 20
The exact answer is 18, close to the estimate.
4.Estimate 54 − 19 by rounding each number to the nearest 10.
Answer: 30
- 54 rounds to 50; 19 rounds to 20
- 50 − 20 = 30
The exact answer is 35, close to the estimate.
5.Estimate 28 + 15 by rounding each number to the nearest 10.
Answer: 50
- 28 rounds to 30; 15 rounds to 20
- 30 + 20 = 50
The exact answer is 43, close to the estimate.
6.Estimate 83 + 48 by rounding each number to the nearest 10.
Answer: 130
- 83 rounds to 80; 48 rounds to 50
- 80 + 50 = 130
The exact answer is 131, close to the estimate.
7.Estimate 86 − 76 by rounding each number to the nearest 10.
Answer: 10
- 86 rounds to 90; 76 rounds to 80
- 90 − 80 = 10
The exact answer is 10, close to the estimate.
8.Estimate 14 + 77 by rounding each number to the nearest 10.
Answer: 90
- 14 rounds to 10; 77 rounds to 80
- 10 + 80 = 90
The exact answer is 91, close to the estimate.
9.Estimate 68 + 31 by rounding each number to the nearest 10.
Answer: 100
- 68 rounds to 70; 31 rounds to 30
- 70 + 30 = 100
The exact answer is 99, close to the estimate.
10.Estimate 66 + 56 by rounding each number to the nearest 10.
Answer: 130
- 66 rounds to 70; 56 rounds to 60
- 70 + 60 = 130
The exact answer is 122, close to the estimate.
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.