Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 420 · 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. 1.539 − 358 =
2. 2.980 − 359 =
3. 3.443 − 298 =
4. 4.326 − 297 =
5. 5.976 − 698 =
6. 6.976 − 428 =
7. 7.991 − 697 =
8. 8.819 − 287 =
9. 9.224 − 199 =
10. 10.985 − 798 =
11. 11.862 − 599 =
12. 12.717 − 699 =
13. 13.989 − 229 =
14. 14.655 − 398 =
15. 15.695 − 328 =
16. 16.737 − 569 =
17. 17.803 − 177 =
18. 18.732 − 397 =
19. 19.750 − 597 =
20. 20.586 − 257 =
21. 21.957 − 617 =
22. 22.984 − 658 =
23. 23.761 − 698 =
24. 24.336 − 227 =
25. 25.817 − 669 =
26. 26.600 − 319 =
27. 27.992 − 799 =
28. 28.873 − 197 =
29. 29.621 − 597 =
30. 30.826 − 698 =
31. 31.522 − 467 =
32. 32.980 − 399 =
33. 33.579 − 499 =
34. 34.984 − 689 =
35. 35.854 − 667 =
36. 36.977 − 597 =
37. 37.849 − 397 =
38. 38.917 − 599 =
39. 39.799 − 299 =
40. 40.551 − 497 =

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