| ( | 60 | − | ( | ( | x | − | 200 | ) | ÷ | 10 | ) | ) | ( | x | − | 20 | ) | = | 15210 |
| Left side of the equation = | 60 | ( | x | − | 20 | ) | − | ( | ( | x | − | 200 | ) | ÷ | 10 | ) | ( | x | − | 20 | ) |
| = | 60 | x | − | 60 | × | 20 | − | ( | ( | x | − | 200 | ) | ÷ | 10 | ) | ( | x | − | 20 | ) |
| = | 60 | x | − | 1200 | − | ( | ( | x | − | 200 | ) | ÷ | 10 | ) | ( | x | − | 20 | ) |
| = | 60 | x | − | 1200 | − | ( | x | − | 200 | ) | ÷ | 10 | × | ( | x | − | 20 | ) |
| = | 60 | x | − | 1200 | − | x | × | 1 10 | ( | x | − | 20 | ) | + | 200 | × | 1 10 | ( | x | − | 20 | ) |
| = | 60 | x | − | 1200 | − | x | × | 1 10 | ( | x | − | 20 | ) | + | 20 | ( | x | − | 20 | ) |
| = | 60 | x | − | 1200 | − | x | × | 1 10 | x | + | x | × | 1 10 | × | 20 | + | 20 | ( | x | − | 20 | ) |
| = | 60 | x | − | 1200 | − | x | × | 1 10 | x | + | x | × | 2 | + | 20 | ( | x | − | 20 | ) |
| = | 62 | x | − | 1200 | − | x | × | 1 10 | x | + | 20 | ( | x | − | 20 | ) |
| = | 62 | x | − | 1200 | − | x | × | 1 10 | x | + | 20 | x | − | 20 | × | 20 |
| = | 62 | x | − | 1200 | − | x | × | 1 10 | x | + | 20 | x | − | 400 |
| = | 82 | x | − | 1600 | − | x | × | 1 10 | x |
| 82 | x | − | 1600 | − | x | × | 1 10 | x | = | 15210 |