10 100 | X | + | ( | 100 | − | X | ) | × | 5 100 | = | 100 | × | 6 100 |
| Left side of the equation = | 10 100 | X | + | 100 | × | 5 100 | − | X | × | 5 100 |
| = | 10 100 | X | + | 5 | − | X | × | 5 100 |
| = | 1 20 | X | + | 5 |
1 20 | X | + | 5 | = | 100 | × | 6 100 |
| Right side of the equation = | 6 |
1 20 | X | + | 5 | = | 6 |
1 20 | X | = | 6 | − | 5 |
1 20 | X | = | 1 |
| X | = | 1 | ÷ | 1 20 |
| = | 1 | × | 20 |
| X | = | 20 |