| ( | 402 | − | X | ) | ÷ | X | = | - | 4879 10000 |
| 方程两边同时乘以: | X |
| ( | 402 | − | X | ) | = | - | 4879 10000 | X |
| 402 | − | X | = | - | 4879 10000 | X |
| - | X | + | 4879 10000 | X | = | - | 402 |
| - | 5121 10000 | X | = | - | 402 |
| 402 | = | 5121 10000 | X |
5121 10000 | X | = | 402 |
| X | = | 402 | ÷ | 5121 10000 |
| = | 402 | × | 10000 5121 |
| = | 134 | × | 10000 1707 |
| X | = | 1340000 1707 |
| X | = | 785.002929 |