| X | ÷ | 1000 | + | ( | 68 | − | X | ) | ÷ | 1650 | + | 20 | ÷ | 6679 50 | + | 2 | ÷ | 53 | = | 1 5 |
| 方程左边 = | X | × | 1 1000 | + | ( | 68 | − | X | ) | × | 1 1650 | + | 1000 6679 | + | 2 53 |
| = | 1 1000 | X | + | ( | 68 | − | X | ) | × | 1 1650 | + | 66358 353987 |
1 1000 | X | + | ( | 68 | − | X | ) | × | 1 1650 | + | 66358 353987 | = | 1 5 |
| 方程左边 = | 1 1000 | X | + | 68 | × | 1 1650 | − | X | × | 1 1650 | + | 66358 353987 |
| = | 1 1000 | X | + | 34 825 | − | X | × | 1 1650 | + | 66358 353987 |
| = | 13 33000 | X | + | 66780908 292039275 |
13 33000 | X | + | 66780908 292039275 | = | 1 5 |
13 33000 | X | = | 1 5 | − | 66780908 292039275 |
13 33000 | X | = | - | 8373053 292039275 |
| X | = | - | 8373053 292039275 | ÷ | 13 33000 |
| = | - | 8373053 292039275 | × | 33000 13 |
| = | - | 644081 353987 | × | 40 |
| X | = | - | 25763240 353987 |
| X | = | - 72.780187 |