| ( | 101 | + | x | ) | ÷ | ( | 172 | + | x | ) | = | 309 500 |
| 方程两边同时乘以: | ( | 172 | + | x | ) |
| ( | 101 | + | x | ) | = | 309 500 | ( | 172 | + | x | ) |
| 101 | + | x | = | 309 500 | ( | 172 | + | x | ) |
| 101 | + | x | = | 309 500 | × | 172 | + | 309 500 | x |
| 101 | + | x | = | 13287 125 | + | 309 500 | x |
| x | − | 309 500 | x | = | 13287 125 | − | 101 |
191 500 | x | = | 13287 125 | − | 101 |
191 500 | x | = | 662 125 |
| x | = | 662 125 | ÷ | 191 500 |
| = | 662 125 | × | 500 191 |
| = | 662 | × | 4 191 |
| x | = | 2648 191 |
| x | = | 13.863874 |