| X | ÷ | 40 | + | 3 | = | ( | X | − | 40 | ) | ÷ | ( | 40 | × | 3 | ÷ | 5 | ) |
| Multiply both sides of the equation by: | ( | 40 | × | 3 | ÷ | 5 | ) |
| X | ÷ | 40 | × | ( | 40 | × | 3 | ÷ | 5 | ) | + | 3 | ( | 40 | × | 3 | ÷ | 5 | ) | = | ( | X | − | 40 | ) |
| X | ÷ | 40 | × | 40 | × | 3 | ÷ | 5 | + | 3 | ( | 40 | × | 3 | ÷ | 5 | ) | = | ( | X | − | 40 | ) |
| X | ÷ | 40 | × | 40 | × | 3 | ÷ | 5 | + | 3 | ( | 40 | × | 3 | ÷ | 5 | ) | = | X | − | 40 |
| X | × | 3 5 | + | 3 | ( | 40 | × | 3 | ÷ | 5 | ) | = | X | − | 40 |
3 5 | X | + | 3 | × | 40 | × | 3 | ÷ | 5 | = | X | − | 40 |
3 5 | X | + | 72 | = | X | − | 40 |
3 5 | X | − | X | = | - | 40 | − | 72 |
| - | 2 5 | X | = | - | 40 | − | 72 |
| - | 2 5 | X | = | - | 112 |
| 112 | = | 2 5 | X |
2 5 | X | = | 112 |
| X | = | 112 | ÷ | 2 5 |
| = | 112 | × | 5 2 |
| = | 56 | × | 5 |
| X | = | 280 |