| 3 | = | 100 | ( | X | − | 216 | ) | ÷ | ( | X | × | 1000 | ÷ | 100 | ) |
| Multiply both sides of the equation by: | ( | X | × | 1000 | ÷ | 100 | ) |
| 3 | ( | X | × | 1000 | ÷ | 100 | ) | = | 100 | ( | X | − | 216 | ) |
| 3 | X | × | 1000 | ÷ | 100 | = | 100 | ( | X | − | 216 | ) |
| 3 | X | × | 1000 | ÷ | 100 | = | 100 | X | − | 100 | × | 216 |
| 30 | X | = | 100 | X | − | 21600 |
| 30 | X | − | 100 | X | = | - | 21600 |
| - | 70 | X | = | - | 21600 |
| 21600 | = | 70 | X |
| 70 | X | = | 21600 |
| X | = | 21600 | ÷ | 70 |
| = | 21600 | × | 1 70 |
| = | 2160 | × | 1 7 |
| X | = | 2160 7 |
| X | = | 308.571429 |