Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 797 · 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. 1.640 − 477 =
2. 2.713 − 219 =
3. 3.914 − 207 =
4. 4.626 − 398 =
5. 5.909 − 569 =
6. 6.333 − 299 =
7. 7.875 − 798 =
8. 8.685 − 498 =
9. 9.712 − 189 =
10. 10.944 − 299 =
11. 11.900 − 597 =
12. 12.684 − 177 =
13. 13.394 − 167 =
14. 14.718 − 597 =
15. 15.663 − 617 =
16. 16.597 − 467 =
17. 17.415 − 289 =
18. 18.504 − 439 =
19. 19.746 − 679 =
20. 20.566 − 299 =
21. 21.613 − 599 =
22. 22.722 − 599 =
23. 23.641 − 537 =
24. 24.432 − 258 =
25. 25.944 − 329 =
26. 26.970 − 198 =
27. 27.833 − 627 =
28. 28.894 − 798 =
29. 29.971 − 119 =
30. 30.923 − 797 =
31. 31.944 − 699 =
32. 32.416 − 399 =
33. 33.524 − 397 =
34. 34.461 − 397 =
35. 35.643 − 248 =
36. 36.908 − 589 =
37. 37.596 − 498 =
38. 38.913 − 497 =
39. 39.696 − 358 =
40. 40.948 − 198 =

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