| x | = | ( | ( | 1 | ÷ | 2 | ) | ( | 1 | ÷ | 5 | ) | ) | + | ( | ( | 1 | ÷ | 2 | ) | ( | 2 | ÷ | 5 | ) | ) |
| 方程右边 = | ( | 1 | ÷ | 2 | ) | ( | 1 | ÷ | 5 | ) | + | ( | ( | 1 | ÷ | 2 | ) | ( | 2 | ÷ | 5 | ) | ) |
| = | 1 | ÷ | 2 | × | ( | 1 | ÷ | 5 | ) | + | ( | ( | 1 | ÷ | 2 | ) | ( | 2 | ÷ | 5 | ) | ) |
| = | 1 2 | ( | 1 | ÷ | 5 | ) | + | ( | ( | 1 | ÷ | 2 | ) | ( | 2 | ÷ | 5 | ) | ) |
| = | 1 2 | × | 1 | ÷ | 5 | + | ( | ( | 1 | ÷ | 2 | ) | ( | 2 | ÷ | 5 | ) | ) |
| = | 1 10 | + | ( | ( | 1 | ÷ | 2 | ) | ( | 2 | ÷ | 5 | ) | ) |
| = | 1 10 | + | ( | 1 | ÷ | 2 | ) | ( | 2 | ÷ | 5 | ) |
| = | 1 10 | + | 1 | ÷ | 2 | × | ( | 2 | ÷ | 5 | ) |
| = | 1 10 | + | 1 2 | ( | 2 | ÷ | 5 | ) |
| = | 1 10 | + | 1 2 | × | 2 | ÷ | 5 |
| = | 1 10 | + | 1 5 |
| = | 3 10 |
| x | = | 3 10 |