| ( | 510 | ( | 1 | + | 20 100 | ) | ) | + | ( | 7 100 | x | ) | = | x |
| 方程左边 = | 510 | ( | 1 | + | 20 100 | ) | + | ( | 7 100 | x | ) |
| = | 510 | × | 1 | + | 510 | × | 20 100 | + | ( | 7 100 | x | ) |
| = | 510 | + | 102 | + | ( | 7 100 | x | ) |
| = | 612 | + | ( | 7 100 | x | ) |
| = | 612 | + | 7 100 | x |
| 612 | + | 7 100 | x | = | x |
7 100 | x | − | x | = | - | 612 |
| - | 93 100 | x | = | - | 612 |
| 612 | = | 93 100 | x |
93 100 | x | = | 612 |
| x | = | 612 | ÷ | 93 100 |
| = | 612 | × | 100 93 |
| = | 204 | × | 100 31 |
| x | = | 20400 31 |
| x | = | 658.064516 |