| 50 | X | ( | 1 | − | 1 20 | ) | − | 50 | × | 80 | − | 300 | = | 0 |
| Left side of the equation = | 50 | X | ( | 1 | − | 1 20 | ) | − | 4000 | − | 300 |
| = | 50 | X | ( | 1 | − | 1 20 | ) | − | 4300 |
| 50 | X | ( | 1 | − | 1 20 | ) | − | 4300 | = | 0 |
| Left side of the equation = | 50 | X | × | 1 | − | 50 | X | × | 1 20 | − | 4300 |
| = | 50 | X | − | 5 2 | X | − | 4300 |
| = | 95 2 | X | − | 4300 |
95 2 | X | − | 4300 | = | 0 |
95 2 | X | = | 0 | + | 4300 |
95 2 | X | = | 4300 |
| X | = | 4300 | ÷ | 95 2 |
| = | 4300 | × | 2 95 |
| = | 860 | × | 2 19 |
| X | = | 1720 19 |
| X | = | 90.526316 |