Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 789 · 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. 1.954 − 177 =
2. 2.763 − 698 =
3. 3.619 − 219 =
4. 4.931 − 639 =
5. 5.848 − 699 =
6. 6.458 − 259 =
7. 7.900 − 548 =
8. 8.994 − 699 =
9. 9.532 − 497 =
10. 10.739 − 699 =
11. 11.914 − 669 =
12. 12.598 − 398 =
13. 13.933 − 199 =
14. 14.834 − 199 =
15. 15.869 − 399 =
16. 16.316 − 297 =
17. 17.717 − 698 =
18. 18.885 − 499 =
19. 19.741 − 599 =
20. 20.891 − 799 =
21. 21.446 − 298 =
22. 22.643 − 558 =
23. 23.966 − 797 =
24. 24.436 − 197 =
25. 25.616 − 297 =
26. 26.780 − 579 =
27. 27.528 − 497 =
28. 28.846 − 328 =
29. 29.738 − 259 =
30. 30.957 − 619 =
31. 31.762 − 548 =
32. 32.636 − 169 =
33. 33.688 − 258 =
34. 34.770 − 598 =
35. 35.834 − 479 =
36. 36.342 − 288 =
37. 37.666 − 348 =
38. 38.658 − 618 =
39. 39.538 − 499 =
40. 40.990 − 797 =

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