| ( | 1713 5 | − | X | ) | ÷ | ( | X | − | 638 5 | ) | × | 100 | = | 12 5 |
| Multiply both sides of the equation by: | ( | X | − | 638 5 | ) |
| ( | 1713 5 | − | X | ) | × | 100 | = | 12 5 | ( | X | − | 638 5 | ) |
1713 5 | × | 100 | − | X | × | 100 | = | 12 5 | ( | X | − | 638 5 | ) |
1713 5 | × | 100 | − | X | × | 100 | = | 12 5 | X | − | 12 5 | × | 638 5 |
| 34260 | − | X | × | 100 | = | 12 5 | X | − | 7656 25 |
| - | 100 | X | − | 12 5 | X | = | - | 7656 25 | − | 34260 |
| - | 512 5 | X | = | - | 7656 25 | − | 34260 |
| - | 512 5 | X | = | - | 864156 25 |
864156 25 | = | 512 5 | X |
512 5 | X | = | 864156 25 |
| X | = | 864156 25 | ÷ | 512 5 |
| = | 864156 25 | × | 5 512 |
| = | 216039 5 | × | 1 128 |
| X | = | 216039 640 |
| X | = | 337.560938 |