Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 256 · 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. 1.663 − 589 =
2. 2.558 − 458 =
3. 3.788 − 579 =
4. 4.752 − 698 =
5. 5.962 − 319 =
6. 6.970 − 269 =
7. 7.931 − 699 =
8. 8.735 − 597 =
9. 9.771 − 599 =
10. 10.513 − 238 =
11. 11.796 − 698 =
12. 12.445 − 287 =
13. 13.734 − 618 =
14. 14.857 − 698 =
15. 15.815 − 488 =
16. 16.548 − 428 =
17. 17.959 − 497 =
18. 18.946 − 598 =
19. 19.908 − 197 =
20. 20.898 − 639 =
21. 21.671 − 597 =
22. 22.658 − 527 =
23. 23.945 − 197 =
24. 24.651 − 557 =
25. 25.277 − 177 =
26. 26.705 − 597 =
27. 27.756 − 639 =
28. 28.612 − 499 =
29. 29.971 − 697 =
30. 30.776 − 258 =
31. 31.730 − 699 =
32. 32.644 − 329 =
33. 33.226 − 207 =
34. 34.552 − 397 =
35. 35.476 − 199 =
36. 36.948 − 408 =
37. 37.607 − 398 =
38. 38.867 − 698 =
39. 39.902 − 399 =
40. 40.950 − 457 =

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