508 5 | ÷ | ( | 1 | + | X | ÷ | 12 | × | 7 | ) | = | 399 5 |
| Multiply both sides of the equation by: | ( | 1 | + | X | ÷ | 12 | × | 7 | ) |
508 5 | = | 399 5 | ( | 1 | + | X | ÷ | 12 | × | 7 | ) |
508 5 | = | 399 5 | × | 1 | + | 399 5 | X | ÷ | 12 | × | 7 |
508 5 | = | 399 5 | + | 931 20 | X |
| - | 931 20 | X | = | 399 5 | − | 508 5 |
| - | 931 20 | X | = | - | 109 5 |
109 5 | = | 931 20 | X |
931 20 | X | = | 109 5 |
| X | = | 109 5 | ÷ | 931 20 |
| = | 109 5 | × | 20 931 |
| = | 109 | × | 4 931 |
| X | = | 436 931 |
| X | = | 0.468314 |