| 190000 | + | 1 5 | x | × | 10 | = | 100000 | + | 31 50 | x | × | 10 |
| 方程左边 = | 190000 | + | 2 | x |
| 190000 | + | 2 | x | = | 100000 | + | 31 50 | x | × | 10 |
| 方程右边 = | 100000 | + | 31 5 | x |
| 190000 | + | 2 | x | = | 100000 | + | 31 5 | x |
| 2 | x | − | 31 5 | x | = | 100000 | − | 190000 |
| - | 21 5 | x | = | 100000 | − | 190000 |
| - | 21 5 | x | = | - | 90000 |
| 90000 | = | 21 5 | x |
21 5 | x | = | 90000 |
| x | = | 90000 | ÷ | 21 5 |
| = | 90000 | × | 5 21 |
| = | 30000 | × | 5 7 |
| x | = | 150000 7 |
| x | = | 21428.571429 |