| ( | x | ÷ | 1 20 | ) | ÷ | 2 | = | ( | 4500 | − | x | ÷ | 1 50 | ) | ÷ | 4 |
| 方程左边 = | x | ÷ | 1 20 | × | 1 2 |
| = | x | × | 10 |
| 10 | x | = | ( | 4500 | − | x | ÷ | 1 50 | ) | ÷ | 4 |
| 方程右边 = | 4500 | × | 1 4 | − | x | ÷ | 1 50 | × | 1 4 |
| = | 1125 | − | x | × | 25 2 |
| 10 | x | = | 1125 | − | 25 2 | x |
| 10 | x | + | 25 2 | x | = | 1125 |
45 2 | x | = | 1125 |
| x | = | 1125 | ÷ | 45 2 |
| = | 1125 | × | 2 45 |
| = | 25 | × | 2 |
| x | = | 50 |