| ( | X | − | 5000 | − | 20251 20 | ) | × | 1 10 | = | X | − | 20000 |
| 方程左边 = | X | × | 1 10 | − | 5000 | × | 1 10 | − | 20251 20 | × | 1 10 |
| = | X | × | 1 10 | − | 500 | − | 20251 200 |
| = | 1 10 | X | − | 120251 200 |
1 10 | X | − | 120251 200 | = | X | − | 20000 |
1 10 | X | − | X | = | - | 20000 | + | 120251 200 |
| - | 9 10 | X | = | - | 20000 | + | 120251 200 |
| - | 9 10 | X | = | - | 3879749 200 |
3879749 200 | = | 9 10 | X |
9 10 | X | = | 3879749 200 |
| X | = | 3879749 200 | ÷ | 9 10 |
| = | 3879749 200 | × | 10 9 |
| = | 3879749 20 | × | 1 9 |
| X | = | 3879749 180 |
| X | = | 21554.161111 |