| 1 | ÷ | 5 | × | ( | 800 | − | x | ) | = | 240 | − | x |
| Left side of the equation = | 1 5 | ( | 800 | − | x | ) |
1 5 | ( | 800 | − | x | ) | = | 240 | − | x |
| Left side of the equation = | 1 5 | × | 800 | − | 1 5 | x |
| = | 160 | − | 1 5 | x |
| 160 | − | 1 5 | x | = | 240 | − | x |
| - | 1 5 | x | + | x | = | 240 | − | 160 |
| - | - | 4 5 | x | = | 240 | − | 160 |
| - | - | 4 5 | x | = | 80 |
| - | 80 | = | - | 4 5 | x |
| - | 4 5 | x | = | - | 80 |
| x | = | 80 | ÷ | 4 5 |
| = | 80 | × | 5 4 |
| = | 20 | × | 5 |
| x | = | 100 |