| ( | ( | x | × | 3 | × | 7 4 | ) | ÷ | 1500 | ) | ( | ( | x | × | 8 5 | ) | − | 1500 | ) | × | 20 | = | 300000 |
| 方程左边 = | ( | x | × | 3 | × | 7 4 | ) | ÷ | 1500 | × | ( | ( | x | × | 8 5 | ) | − | 1500 | ) | × | 20 |
| = | ( | x | × | 3 | × | 7 4 | ) | × | 1 75 | ( | ( | x | × | 8 5 | ) | − | 1500 | ) |
| = | x | × | 3 | × | 7 4 | × | 1 75 | ( | ( | x | × | 8 5 | ) | − | 1500 | ) |
| = | x | × | 7 100 | ( | ( | x | × | 8 5 | ) | − | 1500 | ) |
| = | x | × | 7 100 | ( | x | × | 8 5 | ) | − | x | × | 7 100 | × | 1500 |
| = | x | × | 7 100 | ( | x | × | 8 5 | ) | − | x | × | 105 |
| = | x | × | 7 100 | x | × | 8 5 | − | 105 | x |
| = | x | × | 14 125 | x | − | 105 | x |
| x | × | 14 125 | x | − | 105 | x | = | 300000 |