| 80 | ÷ | 100 | = | ( | X | − | 5000 | ) | ÷ | 2000 |
| Left side of the equation = | 4 5 |
4 5 | = | ( | X | − | 5000 | ) | ÷ | 2000 |
| Right side of the equation = | X | × | 1 2000 | − | 5000 | × | 1 2000 |
| = | X | × | 1 2000 | − | 5 2 |
4 5 | = | 1 2000 | X | − | 5 2 |
| - | 1 2000 | X | = | - | 5 2 | − | 4 5 |
| - | 1 2000 | X | = | - | 33 10 |
33 10 | = | 1 2000 | X |
1 2000 | X | = | 33 10 |
| X | = | 33 10 | ÷ | 1 2000 |
| = | 33 10 | × | 2000 |
| = | 33 | × | 200 |
| X | = | 6600 |