| 130 | − | X | = | 1 | ÷ | 3 | × | ( | 230 | − | X | ) |
| 方程右边 = | 1 3 | ( | 230 | − | X | ) |
| 130 | − | X | = | 1 3 | ( | 230 | − | X | ) |
| 方程右边 = | 1 3 | × | 230 | − | 1 3 | X |
| = | 230 3 | − | 1 3 | X |
| 130 | − | X | = | 230 3 | − | 1 3 | X |
| - | X | + | 1 3 | X | = | 230 3 | − | 130 |
| - | 2 3 | X | = | 230 3 | − | 130 |
| - | 2 3 | X | = | - | 160 3 |
160 3 | = | 2 3 | X |
2 3 | X | = | 160 3 |
| X | = | 160 3 | ÷ | 2 3 |
| = | 160 3 | × | 3 2 |
| = | 80 | × | 1 |
| X | = | 80 |