| ( | 140 | ( | 1 | + | 15 100 | ) | ) | + | ( | 8 100 | x | ) | = | x |
| Left side of the equation = | 140 | ( | 1 | + | 15 100 | ) | + | ( | 8 100 | x | ) |
| = | 140 | × | 1 | + | 140 | × | 15 100 | + | ( | 8 100 | x | ) |
| = | 140 | + | 21 | + | ( | 8 100 | x | ) |
| = | 161 | + | ( | 8 100 | x | ) |
| = | 161 | + | 8 100 | x |
| 161 | + | 8 100 | x | = | x |
8 100 | x | − | x | = | - | 161 |
| - | 23 25 | x | = | - | 161 |
| 161 | = | 23 25 | x |
23 25 | x | = | 161 |
| x | = | 161 | ÷ | 23 25 |
| = | 161 | × | 25 23 |
| = | 7 | × | 25 |
| x | = | 175 |