Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 269 · 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. 1.731 − 697 =
2. 2.394 − 198 =
3. 3.878 − 629 =
4. 4.833 − 797 =
5. 5.932 − 669 =
6. 6.933 − 297 =
7. 7.875 − 797 =
8. 8.839 − 697 =
9. 9.239 − 197 =
10. 10.918 − 359 =
11. 11.836 − 678 =
12. 12.559 − 297 =
13. 13.775 − 197 =
14. 14.574 − 198 =
15. 15.874 − 597 =
16. 16.803 − 528 =
17. 17.567 − 197 =
18. 18.690 − 597 =
19. 19.705 − 199 =
20. 20.818 − 408 =
21. 21.545 − 519 =
22. 22.689 − 399 =
23. 23.939 − 399 =
24. 24.577 − 439 =
25. 25.780 − 699 =
26. 26.626 − 498 =
27. 27.845 − 167 =
28. 28.331 − 229 =
29. 29.382 − 199 =
30. 30.831 − 698 =
31. 31.864 − 119 =
32. 32.672 − 468 =
33. 33.434 − 239 =
34. 34.927 − 797 =
35. 35.745 − 697 =
36. 36.906 − 697 =
37. 37.687 − 669 =
38. 38.904 − 568 =
39. 39.499 − 397 =
40. 40.582 − 399 =

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