Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 948 · 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. 1.910 − 587 =
2. 2.817 − 499 =
3. 3.355 − 197 =
4. 4.973 − 598 =
5. 5.996 − 198 =
6. 6.688 − 598 =
7. 7.725 − 259 =
8. 8.353 − 339 =
9. 9.608 − 399 =
10. 10.709 − 597 =
11. 11.694 − 497 =
12. 12.877 − 358 =
13. 13.843 − 278 =
14. 14.864 − 797 =
15. 15.707 − 499 =
16. 16.930 − 198 =
17. 17.656 − 448 =
18. 18.963 − 599 =
19. 19.677 − 598 =
20. 20.349 − 197 =
21. 21.353 − 308 =
22. 22.776 − 268 =
23. 23.937 − 497 =
24. 24.696 − 297 =
25. 25.579 − 419 =
26. 26.878 − 597 =
27. 27.311 − 137 =
28. 28.963 − 219 =
29. 29.366 − 157 =
30. 30.899 − 499 =
31. 31.232 − 198 =
32. 32.902 − 598 =
33. 33.902 − 198 =
34. 34.923 − 348 =
35. 35.916 − 599 =
36. 36.783 − 297 =
37. 37.642 − 399 =
38. 38.907 − 699 =
39. 39.689 − 187 =
40. 40.770 − 698 =

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