Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 962 · 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. 1.502 − 467 =
2. 2.468 − 129 =
3. 3.879 − 799 =
4. 4.846 − 498 =
5. 5.551 − 119 =
6. 6.220 − 198 =
7. 7.747 − 529 =
8. 8.629 − 498 =
9. 9.985 − 597 =
10. 10.664 − 298 =
11. 11.660 − 277 =
12. 12.583 − 429 =
13. 13.761 − 637 =
14. 14.564 − 258 =
15. 15.615 − 198 =
16. 16.785 − 698 =
17. 17.341 − 159 =
18. 18.911 − 439 =
19. 19.664 − 168 =
20. 20.453 − 347 =
21. 21.786 − 347 =
22. 22.757 − 629 =
23. 23.669 − 459 =
24. 24.733 − 498 =
25. 25.751 − 179 =
26. 26.627 − 298 =
27. 27.492 − 397 =
28. 28.520 − 359 =
29. 29.249 − 197 =
30. 30.398 − 249 =
31. 31.842 − 799 =
32. 32.365 − 337 =
33. 33.833 − 299 =
34. 34.550 − 497 =
35. 35.950 − 507 =
36. 36.322 − 239 =
37. 37.285 − 177 =
38. 38.607 − 529 =
39. 39.824 − 799 =
40. 40.897 − 338 =

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