Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 337 · 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. 1.949 − 497 =
2. 2.611 − 299 =
3. 3.417 − 199 =
4. 4.681 − 647 =
5. 5.310 − 197 =
6. 6.976 − 799 =
7. 7.588 − 497 =
8. 8.939 − 428 =
9. 9.692 − 299 =
10. 10.216 − 199 =
11. 11.647 − 348 =
12. 12.874 − 797 =
13. 13.552 − 497 =
14. 14.950 − 399 =
15. 15.932 − 369 =
16. 16.658 − 508 =
17. 17.631 − 557 =
18. 18.418 − 269 =
19. 19.507 − 299 =
20. 20.450 − 219 =
21. 21.614 − 317 =
22. 22.682 − 329 =
23. 23.690 − 599 =
24. 24.913 − 398 =
25. 25.848 − 797 =
26. 26.332 − 198 =
27. 27.265 − 189 =
28. 28.575 − 207 =
29. 29.901 − 128 =
30. 30.746 − 379 =
31. 31.701 − 379 =
32. 32.719 − 527 =
33. 33.875 − 799 =
34. 34.983 − 647 =
35. 35.389 − 138 =
36. 36.827 − 209 =
37. 37.411 − 298 =
38. 38.877 − 799 =
39. 39.742 − 298 =
40. 40.884 − 497 =

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