| ( | X | − | 66 | ) | × | 3 4 | ÷ | 450 | = | ( | X | − | 48 | ) | × | 3 4 | ÷ | 460 |
| 方程左边 = | ( | X | − | 66 | ) | × | 1 600 |
| ( | X | − | 66 | ) | × | 1 600 | = | ( | X | − | 48 | ) | × | 3 4 | ÷ | 460 |
| 方程左边 = | X | × | 1 600 | − | 66 | × | 1 600 |
| = | X | × | 1 600 | − | 11 100 |
1 600 | X | − | 11 100 | = | ( | X | − | 48 | ) | × | 3 4 | ÷ | 460 |
| 方程右边 = | ( | X | − | 48 | ) | × | 3 1840 |
1 600 | X | − | 11 100 | = | ( | X | − | 48 | ) | × | 3 1840 |
| 方程右边 = | X | × | 3 1840 | − | 48 | × | 3 1840 |
| = | X | × | 3 1840 | − | 9 115 |
1 600 | X | − | 11 100 | = | 3 1840 | X | − | 9 115 |
1 600 | X | − | 3 1840 | X | = | - | 9 115 | + | 11 100 |
1 27600 | X | = | - | 9 115 | + | 11 100 |
1 27600 | X | = | 73 2300 |
| X | = | 73 2300 | ÷ | 1 27600 |
| = | 73 2300 | × | 27600 |
| = | 73 | × | 12 |
| X | = | 876 |