| - | 12500 | − | ( | 50000 | + | X | ) | × | 3 25 | ÷ | 12 | + | X | = | 5000 |
| 方程左边 = | - | 12500 | − | ( | 50000 | + | X | ) | × | 1 100 | + | X |
| - | 12500 | − | ( | 50000 | + | X | ) | × | 1 100 | + | X | = | 5000 |
| 方程左边 = | - | 12500 | − | 50000 | × | 1 100 | − | X | × | 1 100 | + | X |
| = | - | 12500 | − | 500 | − | X | × | 1 100 | + | X |
| = | - | 13000 | + | 99 100 | X |
| - | 13000 | + | 99 100 | X | = | 5000 |
99 100 | X | = | 5000 | + | 13000 |
99 100 | X | = | 18000 |
| X | = | 18000 | ÷ | 99 100 |
| = | 18000 | × | 100 99 |
| = | 2000 | × | 100 11 |
| X | = | 200000 11 |
| X | = | 18181.818182 |