| ( | 30000 | ÷ | ( | 6 5 | x | ) | ) | + | 20 | = | ( | 30000 | ÷ | x | ) |
| 30000 | ÷ | ( | 6 5 | x | ) | + | 20 | = | ( | 30000 | ÷ | x | ) |
| 30000 | ÷ | ( | 6 5 | x | ) | + | 20 | = | 30000 | ÷ | x |
| 方程两边同时乘以: | ( | 6 5 | x | ) |
| 30000 | + | 20 | ( | 6 5 | x | ) | = | 30000 | ÷ | 1 | × | ( | 6 5 | × | 1 | ) |
| 30000 | + | 20 | × | 6 5 | x | = | 30000 | ÷ | 1 | × | ( | 6 5 | × | 1 | ) |
| 30000 | + | 20 | × | 6 5 | x | = | 30000 | ÷ | 1 | × | 6 5 | × | 1 |
| 30000 | + | 24 | x | = | 36000 |
| 24 | x | = | 36000 | − | 30000 |
| 24 | x | = | 6000 |
| x | = | 6000 | ÷ | 24 |
| = | 6000 | × | 1 24 |
| = | 250 | × | 1 |
| x | = | 250 |