| 1 | ÷ | 50 | × | X | × | 40 | + | 1 | ÷ | 75 | × | ( | 40 | − | X | ) | = | 0 |
| Left side of the equation = | 4 5 | X | + | 1 75 | ( | 40 | − | X | ) |
4 5 | X | + | 1 75 | ( | 40 | − | X | ) | = | 0 |
| Left side of the equation = | 4 5 | X | + | 1 75 | × | 40 | − | 1 75 | X |
| = | 4 5 | X | + | 8 15 | − | 1 75 | X |
| = | 59 75 | X | + | 8 15 |
59 75 | X | + | 8 15 | = | 0 |
59 75 | X | = | 0 | − | 8 15 |
59 75 | X | = | - | 8 15 |
| X | = | - | 8 15 | ÷ | 59 75 |
| = | - | 8 15 | × | 75 59 |
| = | - | 8 | × | 5 59 |
| X | = | - | 40 59 |
| X | = | - 0.677966 |