| ( | 200 | − | 10 | ) | ÷ | ( | 200 | − | 20 | ) | = | 200 | ÷ | ( | 200 | − | x | ) |
| Multiply both sides of the equation by: | ( | 200 | − | 20 | ) | , | ( | 200 | − | x | ) |
| ( | 200 | − | 10 | ) | ( | 200 | − | x | ) | = | 200 | ( | 200 | − | 20 | ) |
| 200 | ( | 200 | − | x | ) | − | 10 | ( | 200 | − | x | ) | = | 200 | ( | 200 | − | 20 | ) |
| 200 | ( | 200 | − | x | ) | − | 10 | ( | 200 | − | x | ) | = | 200 | × | 200 | − | 200 | × | 20 |
| 200 | ( | 200 | − | x | ) | − | 10 | ( | 200 | − | x | ) | = | 40000 | − | 4000 |
| 200 | ( | 200 | − | x | ) | − | 10 | ( | 200 | − | x | ) | = | 36000 |
| 200 | × | 200 | − | 200 | x | − | 10 | ( | 200 | − | x | ) | = | 36000 |
| 40000 | − | 200 | x | − | 10 | ( | 200 | − | x | ) | = | 36000 |
| 40000 | − | 200 | x | − | 10 | × | 200 | + | 10 | x | = | 36000 |
| 40000 | − | 200 | x | − | 2000 | + | 10 | x | = | 36000 |
| 38000 | − | 190 | x | = | 36000 |
| - | 190 | x | = | 36000 | − | 38000 |
| - | 190 | x | = | - | 2000 |
| 2000 | = | 190 | x |
| 190 | x | = | 2000 |
| x | = | 2000 | ÷ | 190 |
| = | 2000 | × | 1 190 |
| = | 200 | × | 1 19 |
| x | = | 200 19 |
| x | = | 10.526316 |