| ( | 79 2500 | − | X | ) | ÷ | X | = | 771 2500 |
| 方程两边同时乘以: | X |
| ( | 79 2500 | − | X | ) | = | 771 2500 | X |
79 2500 | − | X | = | 771 2500 | X |
| - | X | − | 771 2500 | X | = | - | 79 2500 |
| - | 3271 2500 | X | = | - | 79 2500 |
79 2500 | = | 3271 2500 | X |
3271 2500 | X | = | 79 2500 |
| X | = | 79 2500 | ÷ | 3271 2500 |
| = | 79 2500 | × | 2500 3271 |
| = | 79 | × | 1 3271 |
| X | = | 79 3271 |
| X | = | 0.024152 |