| ( | 300 | − | X | ) | × | 12 | − | 720 | = | 1480 |
| Left side of the equation = | 300 | × | 12 | − | X | × | 12 | − | 720 |
| = | 3600 | − | X | × | 12 | − | 720 |
| = | 2880 | − | 12 | X |
| 2880 | − | 12 | X | = | 1480 |
| - | 12 | X | = | 1480 | − | 2880 |
| - | 12 | X | = | - | 1400 |
| 1400 | = | 12 | X |
| 12 | X | = | 1400 |
| X | = | 1400 | ÷ | 12 |
| = | 1400 | × | 1 12 |
| = | 350 | × | 1 3 |
| X | = | 350 3 |
| X | = | 116.666667 |