| 255 | − | ( | 1 | ÷ | 2 | ) | a | = | 2 | ( | 1 | ÷ | 2 | ) | a |
| Left side of the equation = | 255 | − | 1 | ÷ | 2 | × | a |
| = | 255 | − | 1 2 | a |
| 255 | − | 1 2 | a | = | 2 | ( | 1 | ÷ | 2 | ) | a |
| Right side of the equation = | 2 | × | 1 | ÷ | 2 | × | a |
| = | 1 | a |
| 255 | − | 1 2 | a | = | 1 | a |
| - | 1 2 | a | − | 1 | a | = | - | 255 |
| - | 3 2 | a | = | - | 255 |
| 255 | = | 3 2 | a |
3 2 | a | = | 255 |
| a | = | 255 | ÷ | 3 2 |
| = | 255 | × | 2 3 |
| = | 85 | × | 2 |
| a | = | 170 |