Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 271 · 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. 1.567 − 248 =
2. 2.635 − 388 =
3. 3.781 − 198 =
4. 4.963 − 528 =
5. 5.999 − 497 =
6. 6.713 − 238 =
7. 7.763 − 529 =
8. 8.978 − 399 =
9. 9.287 − 197 =
10. 10.769 − 598 =
11. 11.807 − 497 =
12. 12.361 − 139 =
13. 13.918 − 597 =
14. 14.852 − 798 =
15. 15.627 − 497 =
16. 16.537 − 297 =
17. 17.846 − 798 =
18. 18.852 − 158 =
19. 19.936 − 548 =
20. 20.888 − 797 =
21. 21.472 − 119 =
22. 22.722 − 148 =
23. 23.880 − 147 =
24. 24.962 − 197 =
25. 25.859 − 797 =
26. 26.876 − 299 =
27. 27.774 − 628 =
28. 28.735 − 608 =
29. 29.455 − 198 =
30. 30.330 − 129 =
31. 31.562 − 477 =
32. 32.642 − 199 =
33. 33.922 − 398 =
34. 34.863 − 398 =
35. 35.430 − 198 =
36. 36.688 − 629 =
37. 37.943 − 297 =
38. 38.884 − 198 =
39. 39.749 − 649 =
40. 40.921 − 799 =

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