| 10 | x | ÷ | 2 | = | 12 | ( | 27 | − | x | ) | ÷ | 3 |
| Left side of the equation = | 5 | x |
| 5 | x | = | 12 | ( | 27 | − | x | ) | ÷ | 3 |
| Right side of the equation = | 4 | ( | 27 | − | x | ) |
| 5 | x | = | 4 | ( | 27 | − | x | ) |
| Right side of the equation = | 4 | × | 27 | − | 4 | x |
| = | 108 | − | 4 | x |
| 5 | x | = | 108 | − | 4 | x |
| 5 | x | + | 4 | x | = | 108 |
| 9 | x | = | 108 |
| x | = | 108 | ÷ | 9 |
| = | 108 | × | 1 9 |
| = | 12 | × | 1 |
| x | = | 12 |