| X | ÷ | 200 | + | ( | 109 2 | − | X | ) | ÷ | 1000 | = | 13 200 |
| Left side of the equation = | 1 200 | X | + | 109 2 | × | 1 1000 | − | X | × | 1 1000 |
| = | 1 200 | X | + | 109 2000 | − | X | × | 1 1000 |
| = | 1 250 | X | + | 109 2000 |
1 250 | X | + | 109 2000 | = | 13 200 |
1 250 | X | = | 13 200 | − | 109 2000 |
1 250 | X | = | 21 2000 |
| X | = | 21 2000 | ÷ | 1 250 |
| = | 21 2000 | × | 250 |
| = | 21 8 | × | 1 |
| X | = | 21 8 |
| X | = | 2.625 |