| 4200 | × | 11 25 | × | 65 | = | 1 2 | × | 4200 | × | 20 | + | 11 50 | × | 20 | x |
| 方程左边 = | 120120 |
| 120120 | = | 1 2 | × | 4200 | × | 20 | + | 11 50 | × | 20 | x |
| 方程右边 = | 42000 | + | 22 5 | x |
| 120120 | = | 42000 | + | 22 5 | x |
| - | 22 5 | x | = | 42000 | − | 120120 |
| - | 22 5 | x | = | - | 78120 |
| 78120 | = | 22 5 | x |
22 5 | x | = | 78120 |
| x | = | 78120 | ÷ | 22 5 |
| = | 78120 | × | 5 22 |
| = | 39060 | × | 5 11 |
| x | = | 195300 11 |
| x | = | 17754.545455 |