| 27 | × | 80 | − | 27 | t | = | 2 | t | − | 2 | × | 56 |
| 方程左边 = | 2160 | − | 27 | t |
| 2160 | − | 27 | t | = | 2 | t | − | 2 | × | 56 |
| 方程右边 = | 2 | t | − | 112 |
| 2160 | − | 27 | t | = | 2 | t | − | 112 |
| - | 27 | t | − | 2 | t | = | - | 112 | − | 2160 |
| - | 29 | t | = | - | 112 | − | 2160 |
| - | 29 | t | = | - | 2272 |
| 2272 | = | 29 | t |
| 29 | t | = | 2272 |
| t | = | 2272 | ÷ | 29 |
| = | 2272 | × | 1 29 |
| t | = | 2272 29 |
| t | = | 78.344828 |