| ( | 7 20 | − | x | ) | ÷ | ( | 19 20 | − | x | ) | × | 19 20 | ÷ | 7 20 | = | 49 50 |
| 方程两边同时乘以: | ( | 19 20 | − | x | ) |
| ( | 7 20 | − | x | ) | × | 19 20 | ÷ | 7 20 | = | 49 50 | ( | 19 20 | − | x | ) |
7 20 | × | 19 20 | ÷ | 7 20 | − | x | × | 19 20 | ÷ | 7 20 | = | 49 50 | ( | 19 20 | − | x | ) |
7 20 | × | 19 20 | ÷ | 7 20 | − | x | × | 19 20 | ÷ | 7 20 | = | 49 50 | × | 19 20 | − | 49 50 | x |
19 20 | − | x | × | 19 7 | = | 931 1000 | − | 49 50 | x |
| - | 19 7 | x | + | 49 50 | x | = | 931 1000 | − | 19 20 |
| - | 607 350 | x | = | 931 1000 | − | 19 20 |
| - | 607 350 | x | = | - | 19 1000 |
19 1000 | = | 607 350 | x |
607 350 | x | = | 19 1000 |
| x | = | 19 1000 | ÷ | 607 350 |
| = | 19 1000 | × | 350 607 |
| = | 19 20 | × | 7 607 |
| x | = | 133 12140 |
| x | = | 0.010956 |