| X | + | 6 5 | ( | 11 100 | − | X | ) | = | 12 100 |
| 方程左边 = | X | + | 6 5 | × | 11 100 | − | 6 5 | X |
| = | X | + | 33 250 | − | 6 5 | X |
| = | - | 1 5 | X | + | 33 250 |
| - | 1 5 | X | + | 33 250 | = | 12 100 |
| - | 1 5 | X | = | 12 100 | − | 33 250 |
| - | 1 5 | X | = | - | 3 250 |
3 250 | = | 1 5 | X |
1 5 | X | = | 3 250 |
| X | = | 3 250 | ÷ | 1 5 |
| = | 3 250 | × | 5 |
| = | 3 50 | × | 1 |
| X | = | 3 50 |
| X | = | 0.06 |