| ( | X | − | 160 | ) | ÷ | 5 2 | = | ( | X | − | 100 | ) | ÷ | 4 |
| Left side of the equation = | X | × | 2 5 | − | 160 | × | 2 5 |
| = | X | × | 2 5 | − | 64 |
2 5 | X | − | 64 | = | ( | X | − | 100 | ) | ÷ | 4 |
| Right side of the equation = | X | × | 1 4 | − | 100 | × | 1 4 |
| = | X | × | 1 4 | − | 25 |
2 5 | X | − | 64 | = | 1 4 | X | − | 25 |
2 5 | X | − | 1 4 | X | = | - | 25 | + | 64 |
3 20 | X | = | - | 25 | + | 64 |
3 20 | X | = | 39 |
| X | = | 39 | ÷ | 3 20 |
| = | 39 | × | 20 3 |
| = | 13 | × | 20 |
| X | = | 260 |