| 140 | ( | 30 | − | x | ) | − | 110 | x | = | 16 5 |
| 方程左边 = | 140 | × | 30 | − | 140 | x | − | 110 | x |
| = | 4200 | − | 140 | x | − | 110 | x |
| = | 4200 | − | 250 | x |
| 4200 | − | 250 | x | = | 16 5 |
| - | 250 | x | = | 16 5 | − | 4200 |
| - | 250 | x | = | - | 20984 5 |
20984 5 | = | 250 | x |
| 250 | x | = | 20984 5 |
| x | = | 20984 5 | ÷ | 250 |
| = | 20984 5 | × | 1 250 |
| = | 10492 5 | × | 1 125 |
| x | = | 10492 625 |
| x | = | 16.7872 |