| ( | X | − | ( | ( | X | − | X | × | 1 5 | ) | × | 1 5 | ) | ) | ÷ | ( | 1 | + | 3 100 | ) | = | 4000 |
| Multiply both sides of the equation by: | ( | 1 | + | 3 100 | ) |
| ( | X | − | ( | ( | X | − | X | × | 1 5 | ) | × | 1 5 | ) | ) | = | 4000 | ( | 1 | + | 3 100 | ) |
| X | − | ( | ( | X | − | X | × | 1 5 | ) | × | 1 5 | ) | = | 4000 | ( | 1 | + | 3 100 | ) |
| X | − | ( | ( | X | − | X | × | 1 5 | ) | × | 1 5 | ) | = | 4000 | × | 1 | + | 4000 | × | 3 100 |
| X | − | ( | ( | X | − | X | × | 1 5 | ) | × | 1 5 | ) | = | 4000 | + | 120 |
| X | − | ( | ( | X | − | X | × | 1 5 | ) | × | 1 5 | ) | = | 4120 |
| X | − | ( | X | − | X | × | 1 5 | ) | × | 1 5 | = | 4120 |
| X | − | X | × | 1 5 | + | X | × | 1 5 | × | 1 5 | = | 4120 |
| X | − | X | × | 1 5 | + | X | × | 1 25 | = | 4120 |
21 25 | X | = | 4120 |
| X | = | 4120 | ÷ | 21 25 |
| = | 4120 | × | 25 21 |
| X | = | 103000 21 |
| X | = | 4904.761905 |