| X | − | X | ÷ | 21 20 | × | 3 200 | − | X | ÷ | 21 20 | × | 3 200 | × | 7 100 | × | 1 2 | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | × | 1 50 | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | = | 27600 |
| 方程左边 = | X | − | X | × | 1 70 | − | X | × | 1 2000 | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | × | 1 50 | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | × | 1 200 |
| = | 13793 14000 | X | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | × | 1 50 | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | × | 1 200 |
13793 14000 | X | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | × | 1 50 | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | × | 1 200 | = | 27600 |
| 方程左边 = | 13793 14000 | X | − | X | × | 1 50 | + | X | ÷ | 21 20 | × | 3 200 | × | 1 50 | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | × | 1 200 |
| = | 13793 14000 | X | − | X | × | 1 50 | + | X | × | 1 3500 | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | × | 1 200 |
| = | 1931 2000 | X | − | ( | X | − | X | ÷ | 21 20 | × | 3 200 | ) | × | 1 200 |
| = | 1931 2000 | X | − | X | × | 1 200 | + | X | ÷ | 21 20 | × | 3 200 | × | 1 200 |
| = | 1931 2000 | X | − | X | × | 1 200 | + | X | × | 1 14000 |
| = | 1681 1750 | X |
1681 1750 | X | = | 27600 |
| X | = | 27600 | ÷ | 1681 1750 |
| = | 27600 | × | 1750 1681 |
| X | = | 48300000 1681 |
| X | = | 28732.897085 |