| 1200 | ÷ | x | + | 2400 | ÷ | ( | 3 2 | x | ) | = | 10 |
| 方程两边同时乘以: | x |
| 1200 | + | 2400 | ÷ | ( | 3 2 | × | 1 | ) | × | 1 | = | 10 | x |
| 方程两边同时乘以: | ( | 3 2 | × | 1 | ) |
| 1200 | ( | 3 2 | × | 1 | ) | + | 2400 | × | 1 | = | 10 | x | ( | 3 2 | × | 1 | ) |
| 1200 | × | 3 2 | × | 1 | + | 2400 | × | 1 | = | 10 | x | ( | 3 2 | × | 1 | ) |
| 1200 | × | 3 2 | × | 1 | + | 2400 | × | 1 | = | 10 | x | × | 3 2 | × | 1 |
| 1800 | + | 2400 | = | 15 | x |
| 4200 | = | 15 | x |
| - | 15 | x | = | - | 4200 |
| 4200 | = | 15 | x |
| 15 | x | = | 4200 |
| x | = | 4200 | ÷ | 15 |
| = | 4200 | × | 1 15 |
| = | 280 | × | 1 |
| x | = | 280 |