Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 954 · 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. 1.696 − 267 =
2. 2.753 − 599 =
3. 3.463 − 299 =
4. 4.889 − 798 =
5. 5.979 − 359 =
6. 6.924 − 798 =
7. 7.877 − 619 =
8. 8.971 − 497 =
9. 9.851 − 297 =
10. 10.357 − 297 =
11. 11.822 − 699 =
12. 12.839 − 198 =
13. 13.724 − 699 =
14. 14.831 − 299 =
15. 15.882 − 269 =
16. 16.381 − 339 =
17. 17.325 − 297 =
18. 18.919 − 468 =
19. 19.750 − 597 =
20. 20.902 − 597 =
21. 21.700 − 537 =
22. 22.771 − 548 =
23. 23.368 − 198 =
24. 24.802 − 687 =
25. 25.545 − 218 =
26. 26.854 − 409 =
27. 27.920 − 497 =
28. 28.623 − 298 =
29. 29.163 − 128 =
30. 30.503 − 197 =
31. 31.907 − 399 =
32. 32.774 − 498 =
33. 33.561 − 378 =
34. 34.676 − 397 =
35. 35.705 − 538 =
36. 36.548 − 309 =
37. 37.997 − 607 =
38. 38.922 − 797 =
39. 39.621 − 528 =
40. 40.792 − 599 =

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