| ( | 192539 | X | + | 180000 | ) | = | 78 | × | 275000 | X | ÷ | 100 |
| 方程左边 = | 192539 | X | + | 180000 |
| 192539 | X | + | 180000 | = | 78 | × | 275000 | X | ÷ | 100 |
| 方程右边 = | 214500 | X |
| 192539 | X | + | 180000 | = | 214500 | X |
| 192539 | X | − | 214500 | X | = | - | 180000 |
| - | 21961 | X | = | - | 180000 |
| 180000 | = | 21961 | X |
| 21961 | X | = | 180000 |
| X | = | 180000 | ÷ | 21961 |
| = | 180000 | × | 1 21961 |
| X | = | 180000 21961 |
| X | = | 8.196348 |