| X | − | 1 5 | X | − | 1 20 | X | − | 3 | = | 72 5 | + | 1 5 | × | 72 5 |
| Left side of the equation = | 3 4 | X | − | 3 |
3 4 | X | − | 3 | = | 72 5 | + | 1 5 | × | 72 5 |
| Right side of the equation = | 72 5 | + | 72 25 |
| = | 432 25 |
3 4 | X | − | 3 | = | 432 25 |
3 4 | X | = | 432 25 | + | 3 |
3 4 | X | = | 507 25 |
| X | = | 507 25 | ÷ | 3 4 |
| = | 507 25 | × | 4 3 |
| = | 169 25 | × | 4 |
| X | = | 676 25 |
| X | = | 27.04 |