| ( | 187 | + | X | ) | ÷ | ( | 204 | + | X | ) | = | 24 25 |
| 方程两边同时乘以: | ( | 204 | + | X | ) |
| ( | 187 | + | X | ) | = | 24 25 | ( | 204 | + | X | ) |
| 187 | + | X | = | 24 25 | ( | 204 | + | X | ) |
| 187 | + | X | = | 24 25 | × | 204 | + | 24 25 | X |
| 187 | + | X | = | 4896 25 | + | 24 25 | X |
| X | − | 24 25 | X | = | 4896 25 | − | 187 |
1 25 | X | = | 4896 25 | − | 187 |
1 25 | X | = | 221 25 |
| X | = | 221 25 | ÷ | 1 25 |
| = | 221 25 | × | 25 |
| = | 221 | × | 1 |
| X | = | 221 |