| x | = | 5 4 | ( | x | + | 650 | ) | ÷ | 30 | × | 40 | − | 1250 |
| 方程右边 = | 5 3 | ( | x | + | 650 | ) | − | 1250 |
| x | = | 5 3 | ( | x | + | 650 | ) | − | 1250 |
| 方程右边 = | 5 3 | x | + | 5 3 | × | 650 | − | 1250 |
| = | 5 3 | x | + | 3250 3 | − | 1250 |
| = | 5 3 | x | − | 500 3 |
| x | = | 5 3 | x | − | 500 3 |
| x | − | 5 3 | x | = | - | 500 3 |
| - | 2 3 | x | = | - | 500 3 |
500 3 | = | 2 3 | x |
2 3 | x | = | 500 3 |
| x | = | 500 3 | ÷ | 2 3 |
| = | 500 3 | × | 3 2 |
| = | 250 | × | 1 |
| x | = | 250 |