| 50 | = | a | × | 50 100 | + | ( | 500 | − | a | ) | × | 5 100 |
| Right side of the equation = | 50 100 | a | + | 500 | × | 5 100 | − | a | × | 5 100 |
| = | 50 100 | a | + | 25 | − | a | × | 5 100 |
| = | 9 20 | a | + | 25 |
| 50 | = | 9 20 | a | + | 25 |
| - | 9 20 | a | = | 25 | − | 50 |
| - | 9 20 | a | = | - | 25 |
| 25 | = | 9 20 | a |
9 20 | a | = | 25 |
| a | = | 25 | ÷ | 9 20 |
| = | 25 | × | 20 9 |
| a | = | 500 9 |
| a | = | 55.555556 |