Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 643 · 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. 1.952 − 577 =
2. 2.781 − 437 =
3. 3.763 − 639 =
4. 4.913 − 607 =
5. 5.583 − 238 =
6. 6.743 − 298 =
7. 7.296 − 199 =
8. 8.644 − 609 =
9. 9.306 − 198 =
10. 10.524 − 417 =
11. 11.824 − 559 =
12. 12.846 − 699 =
13. 13.985 − 699 =
14. 14.513 − 219 =
15. 15.986 − 798 =
16. 16.316 − 247 =
17. 17.474 − 197 =
18. 18.942 − 398 =
19. 19.642 − 478 =
20. 20.584 − 298 =
21. 21.957 − 498 =
22. 22.759 − 337 =
23. 23.767 − 327 =
24. 24.833 − 648 =
25. 25.548 − 387 =
26. 26.360 − 199 =
27. 27.534 − 397 =
28. 28.973 − 699 =
29. 29.530 − 229 =
30. 30.642 − 499 =
31. 31.889 − 609 =
32. 32.974 − 528 =
33. 33.849 − 398 =
34. 34.172 − 138 =
35. 35.766 − 468 =
36. 36.936 − 799 =
37. 37.611 − 568 =
38. 38.794 − 197 =
39. 39.991 − 598 =
40. 40.897 − 418 =

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