| 120000 | ÷ | x | − | 100000 | ÷ | x | − | 1 | = | 1000 |
| 方程两边同时乘以: | x |
| 120000 | − | 100000 | ÷ | 1 | × | 1 | − | 1 | x | = | 1000 | x |
| - | 1 | x | − | 1000 | x | = | - | 120000 | + | 100000 | ÷ | 1 | × | 1 |
| - | 1 | x | − | 1000 | x | = | - | 120000 | + | 100000 |
| - | 1001 | x | = | - | 120000 | + | 100000 |
| - | 1001 | x | = | - | 20000 |
| 20000 | = | 1001 | x |
| 1001 | x | = | 20000 |
| x | = | 20000 | ÷ | 1001 |
| = | 20000 | × | 1 1001 |
| x | = | 20000 1001 |
| x | = | 19.98002 |