| ( | 100 | ( | 1 | + | 20 100 | ) | ) | + | ( | 8 100 | x | ) | = | x |
| Left side of the equation = | 100 | ( | 1 | + | 20 100 | ) | + | ( | 8 100 | x | ) |
| = | 100 | × | 1 | + | 100 | × | 20 100 | + | ( | 8 100 | x | ) |
| = | 100 | + | 20 | + | ( | 8 100 | x | ) |
| = | 120 | + | ( | 8 100 | x | ) |
| = | 120 | + | 8 100 | x |
| 120 | + | 8 100 | x | = | x |
8 100 | x | − | x | = | - | 120 |
| - | 23 25 | x | = | - | 120 |
| 120 | = | 23 25 | x |
23 25 | x | = | 120 |
| x | = | 120 | ÷ | 23 25 |
| = | 120 | × | 25 23 |
| x | = | 3000 23 |
| x | = | 130.434783 |