| x | + | ( | 100 100 | − | x | ) | × | 20 100 | = | 92 100 |
| Left side of the equation = | x | + | 100 100 | × | 20 100 | − | x | × | 20 100 |
| = | x | + | 1 5 | − | x | × | 20 100 |
| = | 4 5 | x | + | 1 5 |
4 5 | x | + | 1 5 | = | 92 100 |
4 5 | x | = | 92 100 | − | 1 5 |
4 5 | x | = | 18 25 |
| x | = | 18 25 | ÷ | 4 5 |
| = | 18 25 | × | 5 4 |
| = | 9 5 | × | 1 2 |
| x | = | 9 10 |
| x | = | 0.9 |