| 25 | t | ÷ | 2 | − | 80 | = | 3 | ( | 150 | − | 10 | t | ) |
| 方程左边 = | 25 2 | t | − | 80 |
25 2 | t | − | 80 | = | 3 | ( | 150 | − | 10 | t | ) |
| 方程右边 = | 3 | × | 150 | − | 3 | × | 10 | t |
| = | 450 | − | 30 | t |
25 2 | t | − | 80 | = | 450 | − | 30 | t |
25 2 | t | + | 30 | t | = | 450 | + | 80 |
85 2 | t | = | 450 | + | 80 |
85 2 | t | = | 530 |
| t | = | 530 | ÷ | 85 2 |
| = | 530 | × | 2 85 |
| = | 106 | × | 2 17 |
| t | = | 212 17 |
| t | = | 12.470588 |