| ( | 12813 500 | + | x | ) | × | 43 20 | = | 51253 1000 | + | 71679 1000 | − | x |
| 方程左边 = | 12813 500 | × | 43 20 | + | x | × | 43 20 |
| = | 550959 10000 | + | x | × | 43 20 |
550959 10000 | + | 43 20 | x | = | 51253 1000 | + | 71679 1000 | − | x |
| 方程右边 = | 30733 250 | − | x |
550959 10000 | + | 43 20 | x | = | 30733 250 | − | x |
43 20 | x | + | x | = | 30733 250 | − | 550959 10000 |
63 20 | x | = | 30733 250 | − | 550959 10000 |
63 20 | x | = | 678361 10000 |
| x | = | 678361 10000 | ÷ | 63 20 |
| = | 678361 10000 | × | 20 63 |
| = | 678361 500 | × | 1 63 |
| x | = | 678361 31500 |
| x | = | 21.53527 |