| x | × | 4 100 | × | 20 | + | x | = | 10000 | ( | 20 | − | 6 | + | 1 | ) |
| 方程左边 = | x | × | 4 5 | + | x |
| = | 9 5 | x |
9 5 | x | = | 10000 | ( | 20 | − | 6 | + | 1 | ) |
| 方程右边 = | 10000 | × | 20 | − | 10000 | × | 6 | + | 10000 | × | 1 |
| = | 200000 | − | 60000 | + | 10000 |
| = | 150000 |
9 5 | x | = | 150000 |
| x | = | 150000 | ÷ | 9 5 |
| = | 150000 | × | 5 9 |
| = | 50000 | × | 5 3 |
| x | = | 250000 3 |
| x | = | 83333.333333 |