| X | − | 1 5 | X | − | 1 20 | X | − | 3 | = | 69 | + | 1 5 | × | 69 |
| Left side of the equation = | 3 4 | X | − | 3 |
3 4 | X | − | 3 | = | 69 | + | 1 5 | × | 69 |
| Right side of the equation = | 69 | + | 69 5 |
| = | 414 5 |
3 4 | X | − | 3 | = | 414 5 |
3 4 | X | = | 414 5 | + | 3 |
3 4 | X | = | 429 5 |
| X | = | 429 5 | ÷ | 3 4 |
| = | 429 5 | × | 4 3 |
| = | 143 5 | × | 4 |
| X | = | 572 5 |
| X | = | 114.4 |