| ( | X | + | 6 | ) | ÷ | ( | X | + | 100 | ) | = | 7 20 |
| Multiply both sides of the equation by: | ( | X | + | 100 | ) |
| ( | X | + | 6 | ) | = | 7 20 | ( | X | + | 100 | ) |
| X | + | 6 | = | 7 20 | ( | X | + | 100 | ) |
| X | + | 6 | = | 7 20 | X | + | 7 20 | × | 100 |
| X | + | 6 | = | 7 20 | X | + | 35 |
| X | − | 7 20 | X | = | 35 | − | 6 |
13 20 | X | = | 35 | − | 6 |
13 20 | X | = | 29 |
| X | = | 29 | ÷ | 13 20 |
| = | 29 | × | 20 13 |
| X | = | 580 13 |
| X | = | 44.615385 |