| 100 | ( | 1 | + | x% | ) | = | 85 | ( | 1 | + | ( | x | + | 24 | ) | × | 1 100 | ) |
| 方程左边 = | 100 | × | 1 | + | 100 | × | x% |
| = | 100 | + | 1 | x |
| 100 | + | 1 | x | = | 85 | ( | 1 | + | ( | x | + | 24 | ) | × | 1 100 | ) |
| 方程右边 = | 85 | × | 1 | + | 85 | ( | x | + | 24 | ) | × | 1 100 |
| = | 85 | + | 17 20 | ( | x | + | 24 | ) |
| = | 85 | + | 17 20 | x | + | 17 20 | × | 24 |
| = | 85 | + | 17 20 | x | + | 102 5 |
| = | 527 5 | + | 17 20 | x |
| 100 | + | 1 | x | = | 527 5 | + | 17 20 | x |
| 1 | x | − | 17 20 | x | = | 527 5 | − | 100 |
3 20 | x | = | 527 5 | − | 100 |
3 20 | x | = | 27 5 |
| x | = | 27 5 | ÷ | 3 20 |
| = | 27 5 | × | 20 3 |
| = | 9 | × | 4 |
| x | = | 36 |