| 150 | ( | 100 | − | ( | X | − | 300 | ÷ | 50 | ) | ) | = | 0 |
| Left side of the equation = | 150 | × | 100 | − | 150 | ( | X | − | 300 | ÷ | 50 | ) |
| = | 15000 | − | 150 | ( | X | − | 300 | ÷ | 50 | ) |
| = | 15000 | − | 150 | X | + | 150 | × | 300 | ÷ | 50 |
| = | 15000 | − | 150 | X | + | 900 |
| = | 15900 | − | 150 | X |
| 15900 | − | 150 | X | = | 0 |
| - | 150 | X | = | 0 | − | 15900 |
| - | 150 | X | = | - | 15900 |
| 15900 | = | 150 | X |
| 150 | X | = | 15900 |
| X | = | 15900 | ÷ | 150 |
| = | 15900 | × | 1 150 |
| = | 106 | × | 1 |
| X | = | 106 |