| 30000 | + | 1 1000 | X | + | 16500 | + | 9 5000 | X | + | 16500 | + | 1 1000 | X | + | 5500 | + | 1 5000 | X | = | 1 80 |
| 方程左边 = | 68500 | + | 1 250 | X |
| 68500 | + | 1 250 | X | = | 1 80 |
1 250 | X | = | 1 80 | − | 68500 |
1 250 | X | = | - | 5479999 80 |
| X | = | - | 5479999 80 | ÷ | 1 250 |
| = | - | 5479999 80 | × | 250 |
| = | - | 5479999 8 | × | 25 |
| X | = | - | 136999975 8 |
| X | = | - 17124996.875 |