| ( | 4500 | × | 12 | × | 9 10 | − | 60 100 | × | 70 | X | × | 139 2000 | ) | ÷ | ( | 40 100 | × | 70 | X | + | 5 100 | × | 70 | X | ) | = | 19 500 |
| 方程两边同时乘以: | ( | 40 100 | × | 70 | X | + | 5 100 | × | 70 | X | ) |
| ( | 4500 | × | 12 | × | 9 10 | − | 60 100 | × | 70 | X | × | 139 2000 | ) | = | 19 500 | ( | 40 100 | × | 70 | X | + | 5 100 | × | 70 | X | ) |
| 4500 | × | 12 | × | 9 10 | − | 60 100 | × | 70 | X | × | 139 2000 | = | 19 500 | ( | 40 100 | × | 70 | X | + | 5 100 | × | 70 | X | ) |
| 4500 | × | 12 | × | 9 10 | − | 60 100 | × | 70 | X | × | 139 2000 | = | 19 500 | × | 40 100 | × | 70 | X | + | 19 500 | × | 5 100 | × | 70 | X |
| 48600 | − | 2919 1000 | X | = | 133 125 | X | + | 133 1000 | X |
| 48600 | − | 2919 1000 | X | = | 1197 1000 | X |
| - | 2919 1000 | X | − | 1197 1000 | X | = | - | 48600 |
| - | 1029 250 | X | = | - | 48600 |
| 48600 | = | 1029 250 | X |
1029 250 | X | = | 48600 |
| X | = | 48600 | ÷ | 1029 250 |
| = | 48600 | × | 250 1029 |
| = | 16200 | × | 250 343 |
| X | = | 4050000 343 |
| X | = | 11807.580175 |