| 2750 | + | 22000 | ÷ | 21 | = | ( | 247 | ÷ | 21 | ) | y |
| 方程左边 = | 2750 | + | 22000 21 |
| = | 79750 21 |
79750 21 | = | ( | 247 | ÷ | 21 | ) | y |
| 方程右边 = | 247 | ÷ | 21 | × | y |
| = | 247 21 | y |
79750 21 | = | 247 21 | y |
| - | 247 21 | y | = | - | 79750 21 |
79750 21 | = | 247 21 | y |
247 21 | y | = | 79750 21 |
| y | = | 79750 21 | ÷ | 247 21 |
| = | 79750 21 | × | 21 247 |
| = | 79750 | × | 1 247 |
| y | = | 79750 247 |
| y | = | 322.874494 |