Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 206 · 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. 1.887 − 698 =
2. 2.637 − 599 =
3. 3.597 − 147 =
4. 4.533 − 209 =
5. 5.729 − 679 =
6. 6.574 − 539 =
7. 7.928 − 697 =
8. 8.770 − 598 =
9. 9.616 − 599 =
10. 10.694 − 599 =
11. 11.914 − 697 =
12. 12.605 − 299 =
13. 13.902 − 498 =
14. 14.385 − 359 =
15. 15.834 − 188 =
16. 16.580 − 499 =
17. 17.624 − 549 =
18. 18.657 − 487 =
19. 19.692 − 599 =
20. 20.690 − 169 =
21. 21.603 − 119 =
22. 22.871 − 297 =
23. 23.296 − 259 =
24. 24.607 − 199 =
25. 25.589 − 299 =
26. 26.706 − 597 =
27. 27.809 − 427 =
28. 28.635 − 248 =
29. 29.533 − 497 =
30. 30.995 − 197 =
31. 31.921 − 298 =
32. 32.964 − 798 =
33. 33.282 − 168 =
34. 34.393 − 198 =
35. 35.740 − 497 =
36. 36.786 − 699 =
37. 37.407 − 298 =
38. 38.250 − 199 =
39. 39.710 − 299 =
40. 40.856 − 678 =

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