| ( | 330 | + | x | ) | ÷ | 340 | + | 330 | ÷ | 340 | = | 2 |
| 方程左边 = | ( | 330 | + | x | ) | × | 1 340 | + | 33 34 |
| ( | 330 | + | x | ) | × | 1 340 | + | 33 34 | = | 2 |
| 方程左边 = | 330 | × | 1 340 | + | x | × | 1 340 | + | 33 34 |
| = | 33 34 | + | x | × | 1 340 | + | 33 34 |
| = | 33 17 | + | 1 340 | x |
33 17 | + | 1 340 | x | = | 2 |
1 340 | x | = | 2 | − | 33 17 |
1 340 | x | = | 1 17 |
| x | = | 1 17 | ÷ | 1 340 |
| = | 1 17 | × | 340 |
| = | 1 | × | 20 |
| x | = | 20 |