Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 771 · 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. 1.996 − 599 =
2. 2.920 − 198 =
3. 3.821 − 689 =
4. 4.276 − 219 =
5. 5.938 − 487 =
6. 6.706 − 298 =
7. 7.657 − 199 =
8. 8.882 − 498 =
9. 9.731 − 469 =
10. 10.977 − 698 =
11. 11.580 − 498 =
12. 12.511 − 139 =
13. 13.716 − 399 =
14. 14.735 − 348 =
15. 15.418 − 197 =
16. 16.607 − 118 =
17. 17.872 − 599 =
18. 18.918 − 279 =
19. 19.297 − 198 =
20. 20.583 − 448 =
21. 21.591 − 199 =
22. 22.843 − 149 =
23. 23.450 − 367 =
24. 24.906 − 797 =
25. 25.622 − 599 =
26. 26.616 − 479 =
27. 27.983 − 697 =
28. 28.411 − 168 =
29. 29.737 − 199 =
30. 30.334 − 199 =
31. 31.709 − 608 =
32. 32.894 − 318 =
33. 33.632 − 469 =
34. 34.298 − 159 =
35. 35.716 − 699 =
36. 36.705 − 238 =
37. 37.833 − 599 =
38. 38.700 − 599 =
39. 39.740 − 397 =
40. 40.915 − 288 =

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