Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 904 · 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. 1.726 − 498 =
2. 2.526 − 159 =
3. 3.818 − 409 =
4. 4.600 − 297 =
5. 5.616 − 539 =
6. 6.491 − 157 =
7. 7.647 − 599 =
8. 8.546 − 498 =
9. 9.253 − 158 =
10. 10.767 − 598 =
11. 11.917 − 659 =
12. 12.815 − 298 =
13. 13.520 − 399 =
14. 14.720 − 199 =
15. 15.654 − 319 =
16. 16.606 − 397 =
17. 17.994 − 278 =
18. 18.680 − 599 =
19. 19.893 − 699 =
20. 20.475 − 298 =
21. 21.775 − 488 =
22. 22.704 − 197 =
23. 23.739 − 297 =
24. 24.768 − 547 =
25. 25.927 − 588 =
26. 26.876 − 508 =
27. 27.838 − 689 =
28. 28.197 − 167 =
29. 29.655 − 397 =
30. 30.837 − 399 =
31. 31.978 − 398 =
32. 32.657 − 447 =
33. 33.749 − 377 =
34. 34.769 − 697 =
35. 35.771 − 697 =
36. 36.980 − 697 =
37. 37.374 − 297 =
38. 38.917 − 478 =
39. 39.905 − 199 =
40. 40.667 − 297 =

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