Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 80 · 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. 1.995 − 598 =
2. 2.958 − 599 =
3. 3.934 − 499 =
4. 4.690 − 127 =
5. 5.866 − 598 =
6. 6.528 − 499 =
7. 7.676 − 298 =
8. 8.604 − 397 =
9. 9.854 − 417 =
10. 10.920 − 297 =
11. 11.272 − 238 =
12. 12.623 − 577 =
13. 13.463 − 228 =
14. 14.793 − 519 =
15. 15.624 − 509 =
16. 16.863 − 338 =
17. 17.601 − 139 =
18. 18.830 − 399 =
19. 19.450 − 327 =
20. 20.872 − 498 =
21. 21.750 − 649 =
22. 22.325 − 228 =
23. 23.807 − 417 =
24. 24.880 − 199 =
25. 25.898 − 488 =
26. 26.742 − 359 =
27. 27.540 − 157 =
28. 28.358 − 209 =
29. 29.512 − 497 =
30. 30.374 − 319 =
31. 31.668 − 499 =
32. 32.837 − 697 =
33. 33.920 − 398 =
34. 34.684 − 628 =
35. 35.801 − 699 =
36. 36.729 − 598 =
37. 37.916 − 797 =
38. 38.617 − 298 =
39. 39.850 − 567 =
40. 40.990 − 257 =

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