| 3 | ÷ | 5 | × | x | ÷ | 25 | = | x | + | 7 | ÷ | 30 |
| 方程左边 = | 3 125 | x |
3 125 | x | = | x | + | 7 | ÷ | 30 |
| 方程右边 = | x | + | 7 30 |
3 125 | x | = | x | + | 7 30 |
3 125 | x | − | x | = | 7 30 |
| - | 122 125 | x | = | 7 30 |
| - | 7 30 | = | 122 125 | x |
122 125 | x | = | - | 7 30 |
| x | = | - | 7 30 | ÷ | 122 125 |
| = | - | 7 30 | × | 125 122 |
| = | - | 7 6 | × | 25 122 |
| x | = | - | 175 732 |
| x | = | - 0.239071 |