| ( | 500 | − | y | ) | ( | 10 | + | y | ÷ | 25 | ) | = | 5400 |
| Left side of the equation = | 500 | ( | 10 | + | y | ÷ | 25 | ) | − | y | ( | 10 | + | y | ÷ | 25 | ) |
| = | 500 | × | 10 | + | 500 | y | ÷ | 25 | − | y | ( | 10 | + | y | ÷ | 25 | ) |
| = | 5000 | + | 20 | y | − | y | ( | 10 | + | y | ÷ | 25 | ) |
| = | 5000 | + | 20 | y | − | y | × | 10 | − | y | y | ÷ | 25 |
| = | 5000 | + | 10 | y | − | y | y | × | 1 25 |
| 5000 | + | 10 | y | − | y | y | × | 1 25 | = | 5400 |