Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 541 · 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. 1.932 − 699 =
2. 2.747 − 569 =
3. 3.512 − 467 =
4. 4.800 − 238 =
5. 5.839 − 479 =
6. 6.950 − 698 =
7. 7.999 − 389 =
8. 8.887 − 498 =
9. 9.920 − 279 =
10. 10.814 − 478 =
11. 11.895 − 679 =
12. 12.688 − 499 =
13. 13.286 − 239 =
14. 14.540 − 229 =
15. 15.622 − 129 =
16. 16.892 − 598 =
17. 17.443 − 168 =
18. 18.338 − 298 =
19. 19.626 − 608 =
20. 20.431 − 409 =
21. 21.870 − 627 =
22. 22.354 − 149 =
23. 23.614 − 599 =
24. 24.776 − 299 =
25. 25.898 − 599 =
26. 26.436 − 227 =
27. 27.612 − 477 =
28. 28.665 − 599 =
29. 29.901 − 597 =
30. 30.677 − 499 =
31. 31.706 − 308 =
32. 32.632 − 197 =
33. 33.737 − 599 =
34. 34.602 − 517 =
35. 35.865 − 797 =
36. 36.538 − 518 =
37. 37.899 − 799 =
38. 38.581 − 198 =
39. 39.710 − 607 =
40. 40.593 − 578 =

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