| 6 | ÷ | 13 | × | x | − | 5 | ÷ | 12 | × | ( | x | − | 4 | ) | = | 4 |
| Left side of the equation = | 6 13 | x | − | 5 12 | ( | x | − | 4 | ) |
6 13 | x | − | 5 12 | ( | x | − | 4 | ) | = | 4 |
| Left side of the equation = | 6 13 | x | − | 5 12 | x | + | 5 12 | × | 4 |
| = | 6 13 | x | − | 5 12 | x | + | 5 3 |
| = | 7 156 | x | + | 5 3 |
7 156 | x | + | 5 3 | = | 4 |
7 156 | x | = | 4 | − | 5 3 |
7 156 | x | = | 7 3 |
| x | = | 7 3 | ÷ | 7 156 |
| = | 7 3 | × | 156 7 |
| = | 1 | × | 52 |
| x | = | 52 |