Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 187 · 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. 1.752 − 248 =
2. 2.407 − 199 =
3. 3.491 − 199 =
4. 4.996 − 798 =
5. 5.867 − 599 =
6. 6.687 − 398 =
7. 7.789 − 438 =
8. 8.706 − 689 =
9. 9.994 − 398 =
10. 10.949 − 499 =
11. 11.915 − 297 =
12. 12.932 − 199 =
13. 13.776 − 568 =
14. 14.604 − 489 =
15. 15.722 − 699 =
16. 16.867 − 398 =
17. 17.911 − 298 =
18. 18.861 − 498 =
19. 19.561 − 218 =
20. 20.782 − 167 =
21. 21.953 − 697 =
22. 22.868 − 199 =
23. 23.300 − 247 =
24. 24.840 − 299 =
25. 25.919 − 797 =
26. 26.661 − 329 =
27. 27.970 − 637 =
28. 28.939 − 459 =
29. 29.742 − 598 =
30. 30.281 − 167 =
31. 31.742 − 499 =
32. 32.330 − 299 =
33. 33.768 − 399 =
34. 34.702 − 399 =
35. 35.810 − 499 =
36. 36.416 − 227 =
37. 37.822 − 597 =
38. 38.577 − 398 =
39. 39.822 − 798 =
40. 40.986 − 297 =

Free mental maths lessons, practice and worksheets at talentjr.in/mental-maths