| 160 | ( | 1 | + | a | ) | × | 100 | ( | 1 | − | 4 5 | a | ) | = | 16000 |
| Left side of the equation = | 16000 | ( | 1 | + | a | ) | ( | 1 | − | 4 5 | a | ) |
| 16000 | ( | 1 | + | a | ) | ( | 1 | − | 4 5 | a | ) | = | 16000 |
| Left side of the equation = | 16000 | × | 1 | ( | 1 | − | 4 5 | a | ) | + | 16000 | a | ( | 1 | − | 4 5 | a | ) |
| = | 16000 | ( | 1 | − | 4 5 | a | ) | + | 16000 | a | ( | 1 | − | 4 5 | a | ) |
| = | 16000 | × | 1 | − | 16000 | × | 4 5 | a | + | 16000 | a | ( | 1 | − | 4 5 | a | ) |
| = | 16000 | − | 12800 | a | + | 16000 | a | ( | 1 | − | 4 5 | a | ) |
| = | 16000 | − | 12800 | a | + | 16000 | a | × | 1 | − | 16000 | a | × | 4 5 | a |
| = | 16000 | − | 12800 | a | + | 16000 | a | − | 12800 | a | a |
| = | 16000 | + | 3200 | a | − | 12800 | a | a |
| 16000 | + | 3200 | a | − | 12800 | a | a | = | 16000 |
| a1=0 |