| 10000 | X | × | 20 100 | = | 10000 | X | − | 10000 | X | × | 5 100 | − | ( | 100 | × | 10000 | + | 900000 | ) |
| 方程左边 = | 2000 | X |
| 2000 | X | = | 10000 | X | − | 10000 | X | × | 5 100 | − | ( | 100 | × | 10000 | + | 900000 | ) |
| 方程右边 = | 10000 | X | − | 500 | X | − | ( | 100 | × | 10000 | + | 900000 | ) |
| = | 9500 | X | − | ( | 100 | × | 10000 | + | 900000 | ) |
| 2000 | X | = | 9500 | X | − | ( | 100 | × | 10000 | + | 900000 | ) |
| 方程右边 = | 9500 | X | − | 100 | × | 10000 | − | 900000 |
| = | 9500 | X | − | 1000000 | − | 900000 |
| = | 9500 | X | − | 1900000 |
| 2000 | X | = | 9500 | X | − | 1900000 |
| 2000 | X | − | 9500 | X | = | - | 1900000 |
| - | 7500 | X | = | - | 1900000 |
| 1900000 | = | 7500 | X |
| 7500 | X | = | 1900000 |
| X | = | 1900000 | ÷ | 7500 |
| = | 1900000 | × | 1 7500 |
| = | 760 | × | 1 3 |
| X | = | 760 3 |
| X | = | 253.333333 |