| X | ÷ | ( | X | + | 300 | ) | × | 100 100 | = | 5 100 |
| Multiply both sides of the equation by: | ( | X | + | 300 | ) |
| X | × | 100 100 | = | 5 100 | ( | X | + | 300 | ) |
| X | × | 100 100 | = | 5 100 | X | + | 5 100 | × | 300 |
| X | × | 100 100 | = | 5 100 | X | + | 15 |
100 100 | X | − | 5 100 | X | = | 15 |
19 20 | X | = | 15 |
| X | = | 15 | ÷ | 19 20 |
| = | 15 | × | 20 19 |
| X | = | 300 19 |
| X | = | 15.789474 |