| 50 | × | 250 | ( | 1 | − | 2 | a | ) | ( | 1 | − | a | ) | + | 250 | ( | 1 | + | a | ) | ( | 1 | − | 5 | ÷ | 2 | × | a | ) | = | 31500 | ÷ | 50 |
| Left side of the equation = | 12500 | ( | 1 | − | 2 | a | ) | ( | 1 | − | a | ) | + | 250 | ( | 1 | + | a | ) | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| 12500 | ( | 1 | − | 2 | a | ) | ( | 1 | − | a | ) | + | 250 | ( | 1 | + | a | ) | ( | 1 | − | 5 | ÷ | 2 | × | a | ) | = | 31500 | ÷ | 50 |
| Left side of the equation = | 12500 | × | 1 | ( | 1 | − | a | ) | − | 12500 | × | 2 | a | ( | 1 | − | a | ) | + | 250 | ( | 1 | + | a | ) | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12500 | ( | 1 | − | a | ) | − | 25000 | a | ( | 1 | − | a | ) | + | 250 | ( | 1 | + | a | ) | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12500 | × | 1 | − | 12500 | a | − | 25000 | a | ( | 1 | − | a | ) | + | 250 | ( | 1 | + | a | ) | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12500 | − | 12500 | a | − | 25000 | a | ( | 1 | − | a | ) | + | 250 | ( | 1 | + | a | ) | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12500 | − | 12500 | a | − | 25000 | a | × | 1 | + | 25000 | a | a | + | 250 | ( | 1 | + | a | ) | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12500 | − | 12500 | a | − | 25000 | a | + | 25000 | a | a | + | 250 | ( | 1 | + | a | ) | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12500 | − | 37500 | a | + | 25000 | a | a | + | 250 | ( | 1 | + | a | ) | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12500 | − | 37500 | a | + | 25000 | a | a | + | 250 | × | 1 | ( | 1 | − | 5 | ÷ | 2 | × | a | ) | + | 250 | a | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12500 | − | 37500 | a | + | 25000 | a | a | + | 250 | ( | 1 | − | 5 | ÷ | 2 | × | a | ) | + | 250 | a | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12500 | − | 37500 | a | + | 25000 | a | a | + | 250 | × | 1 | − | 250 | × | 5 | ÷ | 2 | × | a |
| = | 12500 | − | 37500 | a | + | 25000 | a | a | + | 250 | − | 625 | a | + | 250 | a | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12750 | − | 38125 | a | + | 25000 | a | a | + | 250 | a | ( | 1 | − | 5 | ÷ | 2 | × | a | ) |
| = | 12750 | − | 38125 | a | + | 25000 | a | a | + | 250 | a | × | 1 | − | 250 | a | × | 5 |
| = | 12750 | − | 38125 | a | + | 25000 | a | a | + | 250 | a | − | 625 | a | a |
| = | 12750 | − | 37875 | a | + | 25000 | a | a | − | 625 | a | a |
| 12750 | − | 37875 | a | + | 25000 | a | a | − | 625 | a | a | = | 31500 | ÷ | 50 |
| Right side of the equation = | 630 |
| 12750 | − | 37875 | a | + | 25000 | a | a | − | 625 | a | a | = | 630 |