Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 876 · 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. 1.703 − 418 =
2. 2.898 − 357 =
3. 3.720 − 309 =
4. 4.610 − 469 =
5. 5.347 − 197 =
6. 6.496 − 388 =
7. 7.395 − 297 =
8. 8.928 − 699 =
9. 9.880 − 699 =
10. 10.539 − 447 =
11. 11.582 − 197 =
12. 12.650 − 298 =
13. 13.372 − 149 =
14. 14.766 − 397 =
15. 15.842 − 199 =
16. 16.939 − 597 =
17. 17.602 − 518 =
18. 18.588 − 487 =
19. 19.836 − 429 =
20. 20.839 − 498 =
21. 21.694 − 599 =
22. 22.773 − 327 =
23. 23.942 − 797 =
24. 24.641 − 198 =
25. 25.496 − 297 =
26. 26.622 − 597 =
27. 27.847 − 499 =
28. 28.223 − 199 =
29. 29.322 − 299 =
30. 30.742 − 157 =
31. 31.618 − 599 =
32. 32.708 − 397 =
33. 33.635 − 498 =
34. 34.785 − 297 =
35. 35.780 − 547 =
36. 36.606 − 297 =
37. 37.743 − 627 =
38. 38.725 − 699 =
39. 39.731 − 697 =
40. 40.938 − 297 =

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