| 205 | P | × | 15 100 | = | P | ( | 1 | − | 5 100 | ) | − | 205 |
| 方程左边 = | 123 4 | P |
123 4 | P | = | P | ( | 1 | − | 5 100 | ) | − | 205 |
| 方程右边 = | P | × | 1 | − | P | × | 5 100 | − | 205 |
| = | 19 20 | P | − | 205 |
123 4 | P | = | 19 20 | P | − | 205 |
123 4 | P | − | 19 20 | P | = | - | 205 |
149 5 | P | = | - | 205 |
| P | = | - | 205 | ÷ | 149 5 |
| = | - | 205 | × | 5 149 |
| P | = | - | 1025 149 |
| P | = | - 6.879195 |