| 100 | ÷ | ( | 100 | + | 74 | + | X | ) | = | 11 20 |
| Multiply both sides of the equation by: | ( | 100 | + | 74 | + | X | ) |
| 100 | = | 11 20 | ( | 100 | + | 74 | + | X | ) |
| 100 | = | 11 20 | × | 100 | + | 11 20 | × | 74 | + | 11 20 | X |
| 100 | = | 55 | + | 407 10 | + | 11 20 | X |
| 100 | = | 957 10 | + | 11 20 | X |
| - | 11 20 | X | = | 957 10 | − | 100 |
| - | 11 20 | X | = | - | 43 10 |
43 10 | = | 11 20 | X |
11 20 | X | = | 43 10 |
| X | = | 43 10 | ÷ | 11 20 |
| = | 43 10 | × | 20 11 |
| = | 43 | × | 2 11 |
| X | = | 86 11 |
| X | = | 7.818182 |