| 900000 | = | 50000 | ( | 30 | − | X | ) | − | 200000 |
| Right side of the equation = | 50000 | × | 30 | − | 50000 | X | − | 200000 |
| = | 1500000 | − | 50000 | X | − | 200000 |
| = | 1300000 | − | 50000 | X |
| 900000 | = | 1300000 | − | 50000 | X |
| 50000 | X | = | 1300000 | − | 900000 |
| 50000 | X | = | 400000 |
| X | = | 400000 | ÷ | 50000 |
| = | 400000 | × | 1 50000 |
| = | 8 | × | 1 |
| X | = | 8 |