Let's solve the
"Estimating Products" worksheet step by step.
Instructions:
> Round each whole number to the nearest ten, then multiply the rounded numbers to estimate the product.
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We’ll go through each problem one by one:
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1.
42 × 15 →
- 42 → 40 (nearest ten)
- 15 → 20 (nearest ten)
- 40 × 20 =
800
2.
63 × 27 →
- 63 → 60
- 27 → 30
- 60 × 30 =
1,800
3.
12 × 45 →
- 12 → 10
- 45 → 50
- 10 × 50 =
500
4.
32 × 43 →
- 32 → 30
- 43 → 40
- 30 × 40 =
1,200
5.
25 × 12 →
- 25 → 30
- 12 → 10
- 30 × 10 =
300
6.
42 × 21 →
- 42 → 40
- 21 → 20
- 40 × 20 =
800
7.
18 × 12 →
- 18 → 20
- 12 → 10
- 20 × 10 =
200
8.
29 × 15 →
- 29 → 30
- 15 → 20
- 30 × 20 =
600
9.
35 × 19 →
- 35 → 40
- 19 → 20
- 40 × 20 =
800
10.
28 × 12 →
- 28 → 30
- 12 → 10
- 30 × 10 =
300
11.
45 × 33 →
- 45 → 50
- 33 → 30
- 50 × 30 =
1,500
12.
25 × 18 →
- 25 → 30
- 18 → 20
- 30 × 20 =
600
13.
32 × 18 →
- 32 → 30
- 18 → 20
- 30 × 20 =
600
14.
39 × 12 →
- 39 → 40
- 12 → 10
- 40 × 10 =
400
15.
45 × 21 →
- 45 → 50
- 21 → 20
- 50 × 20 =
1,000
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✔ Final Answers:
| Problem | Rounded Numbers | Estimated Product |
|--------|------------------|--------------------|
| 1. | 40 × 20 | 800 |
| 2. | 60 × 30 | 1,800 |
| 3. | 10 × 50 | 500 |
| 4. | 30 × 40 | 1,200 |
| 5. | 30 × 10 | 300 |
| 6. | 40 × 20 | 800 |
| 7. | 20 × 10 | 200 |
| 8. | 30 × 20 | 600 |
| 9. | 40 × 20 | 800 |
| 10. | 30 × 10 | 300 |
| 11. | 50 × 30 | 1,500 |
| 12. | 30 × 20 | 600 |
| 13. | 30 × 20 | 600 |
| 14. | 40 × 10 | 400 |
| 15. | 50 × 20 | 1,000 |
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🔍 Explanation:
-
Rounding to the nearest ten: Look at the ones digit.
- If it's
5 or more, round up.
- If it's
less than 5, round down.
- Example:
- 42 → 40 (ones digit is 2 < 5)
- 45 → 50 (ones digit is 5 → round up)
Then multiply the rounded numbers to get an
estimate of the actual product.
This method helps quickly approximate answers without exact multiplication.
✔ You can now fill in the worksheet with these estimated products!
Parent Tip: Review the logic above to help your child master the concept of estimation multiplication worksheet.
