| ( | 30 | + | 1 10 | X | ) | ÷ | ( | X | − | 30 | − | 1 10 | X | ) | = | 1 | ÷ | 3 |
| Multiply both sides of the equation by: | ( | X | − | 30 | − | 1 10 | X | ) |
| ( | 30 | + | 1 10 | X | ) | = | 1 | ÷ | 3 | × | ( | X | − | 30 | − | 1 10 | X | ) |
| 30 | + | 1 10 | X | = | 1 | ÷ | 3 | × | ( | X | − | 30 | − | 1 10 | X | ) |
| 30 | + | 1 10 | X | = | 1 | ÷ | 3 | × | X | − | 1 | ÷ | 3 | × | 30 | − | 1 | ÷ | 3 | × | 1 10 | X |
| 30 | + | 1 10 | X | = | 1 3 | X | − | 10 | − | 1 30 | X |
| 30 | + | 1 10 | X | = | 3 10 | X | − | 10 |
1 10 | X | − | 3 10 | X | = | - | 10 | − | 30 |
| - | 1 5 | X | = | - | 10 | − | 30 |
| - | 1 5 | X | = | - | 40 |
| 40 | = | 1 5 | X |
1 5 | X | = | 40 |
| X | = | 40 | ÷ | 1 5 |
| = | 40 | × | 5 |
| X | = | 200 |