| ( | x | ÷ | 4000 | ) | ( | 1 | ÷ | 20 | ) | + | ( | ( | 70000 | − | x | ) | ÷ | 2000 | ) | ( | 1 | ÷ | 30 | ) | + | 1 | = | 0 |
| 方程左边 = | x | ÷ | 4000 | × | ( | 1 | ÷ | 20 | ) | + | ( | ( | 70000 | − | x | ) | ÷ | 2000 | ) | ( | 1 | ÷ | 30 | ) | + | 1 |
| = | x | × | 1 4000 | × | 1 | ÷ | 20 | + | ( | ( | 70000 | − | x | ) | ÷ | 2000 | ) | ( | 1 | ÷ | 30 | ) | + | 1 |
| = | x | × | 1 80000 | + | ( | ( | 70000 | − | x | ) | ÷ | 2000 | ) | ( | 1 | ÷ | 30 | ) | + | 1 |
| = | 1 80000 | x | + | ( | 70000 | − | x | ) | ÷ | 2000 | × | ( | 1 | ÷ | 30 | ) | + | 1 |
| = | 1 80000 | x | + | 70000 | × | 1 2000 | ( | 1 | ÷ | 30 | ) | − | x | × | 1 2000 | ( | 1 | ÷ | 30 | ) | + | 1 |
| = | 1 80000 | x | + | 35 | ( | 1 | ÷ | 30 | ) | − | x | × | 1 2000 | ( | 1 | ÷ | 30 | ) | + | 1 |
| = | 1 80000 | x | + | 35 | × | 1 | ÷ | 30 | − | x | × | 1 2000 | ( | 1 | ÷ | 30 | ) | + | 1 |
| = | 1 80000 | x | + | 7 6 | − | x | × | 1 2000 | ( | 1 | ÷ | 30 | ) | + | 1 |
| = | 1 80000 | x | + | 13 6 | − | x | × | 1 2000 | ( | 1 | ÷ | 30 | ) |
| = | 1 80000 | x | + | 13 6 | − | x | × | 1 2000 | × | 1 | ÷ | 30 |
| = | 1 80000 | x | + | 13 6 | − | x | × | 1 60000 |
| = | - | 1 240000 | x | + | 13 6 |
| - | 1 240000 | x | + | 13 6 | = | 0 |
| - | 1 240000 | x | = | 0 | − | 13 6 |
| - | 1 240000 | x | = | - | 13 6 |
13 6 | = | 1 240000 | x |
1 240000 | x | = | 13 6 |
| x | = | 13 6 | ÷ | 1 240000 |
| = | 13 6 | × | 240000 |
| = | 13 | × | 40000 |
| x | = | 520000 |