用竖式计算.
| 3.5+1.8 | 7.2-3.7 | 8+7.25 |
| 8-7.5 | 1.8+3.45 | 12.3-6.75 |
| 3.45×6 | 54÷3 | 32×5 |
| 420÷6 | 65×3 | 960÷3 |
| 21×9 | 720÷8. |
| 3.5+1.8 | 7.2-3.7 | 8+7.25 |
| 8-7.5 | 1.8+3.45 | 12.3-6.75 |
| 3.45×6 | 54÷3 | 32×5 |
| 420÷6 | 65×3 | 960÷3 |
| 21×9 | 720÷8. |