| X | − | ( | ( | X | − | 68487 100 | − | 5000 | ) | × | 10 100 | ) | = | 8500 |
| 方程左边 = | X | − | ( | X | − | 68487 100 | − | 5000 | ) | × | 10 100 |
| = | X | − | X | × | 10 100 | + | 68487 100 | × | 10 100 | + | 5000 | × | 10 100 |
| = | X | − | X | × | 10 100 | + | 68487 1000 | + | 500 |
| = | 9 10 | X | + | 568487 1000 |
9 10 | X | + | 568487 1000 | = | 8500 |
9 10 | X | = | 8500 | − | 568487 1000 |
9 10 | X | = | 7931513 1000 |
| X | = | 7931513 1000 | ÷ | 9 10 |
| = | 7931513 1000 | × | 10 9 |
| = | 7931513 100 | × | 1 9 |
| X | = | 7931513 900 |
| X | = | 8812.792222 |