Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 792 · 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. 1.472 − 219 =
2. 2.296 − 237 =
3. 3.774 − 249 =
4. 4.560 − 298 =
5. 5.940 − 699 =
6. 6.221 − 198 =
7. 7.928 − 198 =
8. 8.644 − 499 =
9. 9.843 − 598 =
10. 10.848 − 548 =
11. 11.478 − 297 =
12. 12.687 − 657 =
13. 13.742 − 698 =
14. 14.675 − 399 =
15. 15.973 − 638 =
16. 16.330 − 199 =
17. 17.710 − 417 =
18. 18.756 − 498 =
19. 19.501 − 429 =
20. 20.803 − 238 =
21. 21.963 − 499 =
22. 22.582 − 497 =
23. 23.596 − 397 =
24. 24.683 − 598 =
25. 25.738 − 487 =
26. 26.797 − 549 =
27. 27.773 − 699 =
28. 28.991 − 797 =
29. 29.724 − 698 =
30. 30.527 − 248 =
31. 31.829 − 299 =
32. 32.875 − 798 =
33. 33.990 − 678 =
34. 34.980 − 699 =
35. 35.903 − 129 =
36. 36.973 − 598 =
37. 37.668 − 338 =
38. 38.667 − 367 =
39. 39.873 − 649 =
40. 40.888 − 798 =

Free mental maths lessons, practice and worksheets at talentjr.in/mental-maths