| 40 | = | ( | 2000 | + | 10 | ) | ÷ | ( | 1 | − | X | ) | × | X |
| 方程两边同时乘以: | ( | 1 | − | X | ) |
| 40 | ( | 1 | − | X | ) | = | ( | 2000 | + | 10 | ) | X |
| 40 | × | 1 | − | 40 | X | = | ( | 2000 | + | 10 | ) | X |
| 40 | × | 1 | − | 40 | X | = | 2000 | X | + | 10 | X |
| 40 | − | 40 | X | = | 2000 | X | + | 10 | X |
| 40 | − | 40 | X | = | 2010 | X |
| - | 40 | X | − | 2010 | X | = | - | 40 |
| - | 2050 | X | = | - | 40 |
| 40 | = | 2050 | X |
| 2050 | X | = | 40 |
| X | = | 40 | ÷ | 2050 |
| = | 40 | × | 1 2050 |
| = | 4 | × | 1 205 |
| X | = | 4 205 |
| X | = | 0.019512 |