| ( | 16 | − | 5 | − | x | ) | ( | 300 | + | x | ÷ | 2 | × | 120 | ) | = | 3780 |
| Left side of the equation = | 16 | ( | 300 | + | x | ÷ | 2 | × | 120 | ) | − | 5 | ( | 300 | + | x | ÷ | 2 | × | 120 | ) | − | x | ( | 300 | + | x | ÷ | 2 | × | 120 | ) |
| = | 16 | × | 300 | + | 16 | x | ÷ | 2 | × | 120 | − | 5 | ( | 300 | + | x | ÷ | 2 | × | 120 | ) | − | x | ( | 300 | + | x | ÷ | 2 | × | 120 | ) |
| = | 4800 | + | 960 | x | − | 5 | ( | 300 | + | x | ÷ | 2 | × | 120 | ) | − | x | ( | 300 | + | x | ÷ | 2 | × | 120 | ) |
| = | 4800 | + | 960 | x | − | 5 | × | 300 | − | 5 | x | ÷ | 2 | × | 120 | − | x | ( | 300 | + | x | ÷ | 2 | × | 120 | ) |
| = | 4800 | + | 960 | x | − | 1500 | − | 300 | x | − | x | ( | 300 | + | x | ÷ | 2 | × | 120 | ) |
| = | 3300 | + | 660 | x | − | x | ( | 300 | + | x | ÷ | 2 | × | 120 | ) |
| = | 3300 | + | 660 | x | − | x | × | 300 | − | x | x | ÷ | 2 | × | 120 |
| = | 3300 | + | 660 | x | − | x | × | 300 | − | x | x | × | 60 |
| = | 3300 | + | 360 | x | − | x | x | × | 60 |
| 3300 | + | 360 | x | − | x | x | × | 60 | = | 3780 |