1.NBT.5
Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.
| 1. | 10 less, 10 more than 40 | |
| 2. | Which number is 10 more than 18? | |
| 3. | Which number is 10 more than 20? | |
| 4. | Which number is 10 more than 18? | |
| 5. | Which number is 10 more than 11? | |
| 6. | Which number is 10 less than 16? | |
| 7. | Which number is 10 less than 22? | |
| 8. | Which number is 10 more than 89? | |
| 9. | Which number is 10 more than 27? | |
| 10. | Which number is 10 more than 62? | |
| 11. | Which number is 10 less than 45? | |
| 12. | Which number is 10 less than 23? | |
| 13. | Which number is 10 less than 76? | |
| 14. | 10 less, 10 more than 10 | |
| 15. | 10 less, 10 more than 20 | |
| 16. | Which number is 10 more than 10? | |
| 17. | Take 10: 40 - 10 = ? | |
| 18. | What Comes Next? - 10 more than 13 | |
| 19. | What Comes Next? - 10 more than 12 |