| X | ÷ | ( | 299 | − | 40 | + | X | ) | = | 9 10 |
| Multiply both sides of the equation by: | ( | 299 | − | 40 | + | X | ) |
| X | = | 9 10 | ( | 299 | − | 40 | + | X | ) |
| X | = | 9 10 | × | 299 | − | 9 10 | × | 40 | + | 9 10 | X |
| X | = | 2691 10 | − | 36 | + | 9 10 | X |
| X | = | 2331 10 | + | 9 10 | X |
| X | − | 9 10 | X | = | 2331 10 |
1 10 | X | = | 2331 10 |
| X | = | 2331 10 | ÷ | 1 10 |
| = | 2331 10 | × | 10 |
| = | 2331 | × | 1 |
| X | = | 2331 |