Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 917 · 40 questions

How to do it in your head (Round up, add back): Round the number you take away up to the next ten or hundred: 297 → 300 (3 too many). Take away the round number. Add back the extra, because you took away too much.

1. 1.547 − 249 =
2. 2.400 − 179 =
3. 3.874 − 799 =
4. 4.417 − 398 =
5. 5.981 − 229 =
6. 6.982 − 599 =
7. 7.731 − 699 =
8. 8.914 − 599 =
9. 9.765 − 399 =
10. 10.879 − 267 =
11. 11.617 − 597 =
12. 12.665 − 499 =
13. 13.967 − 797 =
14. 14.969 − 598 =
15. 15.548 − 159 =
16. 16.815 − 398 =
17. 17.265 − 198 =
18. 18.803 − 597 =
19. 19.863 − 597 =
20. 20.419 − 297 =
21. 21.705 − 489 =
22. 22.544 − 267 =
23. 23.929 − 698 =
24. 24.570 − 147 =
25. 25.886 − 329 =
26. 26.322 − 197 =
27. 27.419 − 148 =
28. 28.585 − 507 =
29. 29.977 − 499 =
30. 30.874 − 399 =
31. 31.910 − 798 =
32. 32.939 − 598 =
33. 33.864 − 298 =
34. 34.773 − 198 =
35. 35.850 − 598 =
36. 36.969 − 197 =
37. 37.589 − 489 =
38. 38.746 − 658 =
39. 39.455 − 197 =
40. 40.335 − 147 =

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