| ( | 20977 5 | + | 211 10 | y | ) | ÷ | ( | 100 | + | y | ) | = | 43 2 |
| 方程两边同时乘以: | ( | 100 | + | y | ) |
| ( | 20977 5 | + | 211 10 | y | ) | = | 43 2 | ( | 100 | + | y | ) |
20977 5 | + | 211 10 | y | = | 43 2 | ( | 100 | + | y | ) |
20977 5 | + | 211 10 | y | = | 43 2 | × | 100 | + | 43 2 | y |
20977 5 | + | 211 10 | y | = | 2150 | + | 43 2 | y |
211 10 | y | − | 43 2 | y | = | 2150 | − | 20977 5 |
| - | 2 5 | y | = | 2150 | − | 20977 5 |
| - | 2 5 | y | = | - | 10227 5 |
10227 5 | = | 2 5 | y |
2 5 | y | = | 10227 5 |
| y | = | 10227 5 | ÷ | 2 5 |
| = | 10227 5 | × | 5 2 |
| = | 10227 | × | 1 2 |
| y | = | 10227 2 |
| y | = | 5113.5 |