| ( | 20977 5 | + | 19 | y | ) | ÷ | ( | 100 | + | y | ) | = | 191 10 |
| 方程两边同时乘以: | ( | 100 | + | y | ) |
| ( | 20977 5 | + | 19 | y | ) | = | 191 10 | ( | 100 | + | y | ) |
20977 5 | + | 19 | y | = | 191 10 | ( | 100 | + | y | ) |
20977 5 | + | 19 | y | = | 191 10 | × | 100 | + | 191 10 | y |
20977 5 | + | 19 | y | = | 1910 | + | 191 10 | y |
| 19 | y | − | 191 10 | y | = | 1910 | − | 20977 5 |
| - | 1 10 | y | = | 1910 | − | 20977 5 |
| - | 1 10 | y | = | - | 11427 5 |
11427 5 | = | 1 10 | y |
1 10 | y | = | 11427 5 |
| y | = | 11427 5 | ÷ | 1 10 |
| = | 11427 5 | × | 10 |
| = | 11427 | × | 2 |
| y | = | 22854 |