Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 461 · 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. 1.983 − 579 =
2. 2.695 − 659 =
3. 3.543 − 388 =
4. 4.433 − 398 =
5. 5.443 − 297 =
6. 6.378 − 127 =
7. 7.937 − 638 =
8. 8.931 − 799 =
9. 9.374 − 198 =
10. 10.946 − 299 =
11. 11.995 − 699 =
12. 12.845 − 697 =
13. 13.456 − 297 =
14. 14.873 − 299 =
15. 15.886 − 697 =
16. 16.608 − 498 =
17. 17.468 − 299 =
18. 18.957 − 347 =
19. 19.800 − 639 =
20. 20.971 − 697 =
21. 21.502 − 297 =
22. 22.991 − 189 =
23. 23.431 − 298 =
24. 24.823 − 158 =
25. 25.833 − 798 =
26. 26.608 − 497 =
27. 27.854 − 699 =
28. 28.786 − 378 =
29. 29.873 − 799 =
30. 30.623 − 539 =
31. 31.930 − 397 =
32. 32.695 − 297 =
33. 33.857 − 699 =
34. 34.744 − 197 =
35. 35.868 − 798 =
36. 36.836 − 397 =
37. 37.769 − 198 =
38. 38.898 − 559 =
39. 39.597 − 249 =
40. 40.630 − 557 =

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