| 1 | ÷ | 2 | × | x | = | 1 | ÷ | 4 | × | ( | 120 | − | x | ) |
| Left side of the equation = | 1 2 | x |
1 2 | x | = | 1 | ÷ | 4 | × | ( | 120 | − | x | ) |
| Right side of the equation = | 1 4 | ( | 120 | − | x | ) |
1 2 | x | = | 1 4 | ( | 120 | − | x | ) |
| Right side of the equation = | 1 4 | × | 120 | − | 1 4 | x |
| = | 30 | − | 1 4 | x |
1 2 | x | = | 30 | − | 1 4 | x |
1 2 | x | + | 1 4 | x | = | 30 |
3 4 | x | = | 30 |
| x | = | 30 | ÷ | 3 4 |
| = | 30 | × | 4 3 |
| = | 10 | × | 4 |
| x | = | 40 |