Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 528 · 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. 1.726 − 287 =
2. 2.511 − 397 =
3. 3.991 − 197 =
4. 4.940 − 187 =
5. 5.623 − 577 =
6. 6.954 − 798 =
7. 7.954 − 127 =
8. 8.678 − 548 =
9. 9.597 − 498 =
10. 10.994 − 399 =
11. 11.964 − 399 =
12. 12.646 − 299 =
13. 13.708 − 448 =
14. 14.897 − 478 =
15. 15.592 − 398 =
16. 16.819 − 288 =
17. 17.841 − 798 =
18. 18.555 − 398 =
19. 19.885 − 799 =
20. 20.936 − 507 =
21. 21.851 − 799 =
22. 22.613 − 358 =
23. 23.788 − 397 =
24. 24.397 − 169 =
25. 25.820 − 197 =
26. 26.980 − 448 =
27. 27.346 − 328 =
28. 28.393 − 299 =
29. 29.750 − 597 =
30. 30.991 − 387 =
31. 31.704 − 377 =
32. 32.883 − 499 =
33. 33.718 − 508 =
34. 34.883 − 498 =
35. 35.761 − 197 =
36. 36.585 − 478 =
37. 37.618 − 299 =
38. 38.680 − 619 =
39. 39.732 − 697 =
40. 40.432 − 199 =

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