| ( | 6 5 | + | 0 | ÷ | 1000 | + | X | ÷ | 1650 | + | 140 | ÷ | 108 | ) | × | 1000 | = | 3 | ( | 550 | + | X | ) |
| 方程左边 = | 6 5 | × | 1000 | + | 0 | ÷ | 1000 | × | 1000 | + | X | ÷ | 1650 | × | 1000 | + | 140 | ÷ | 108 | × | 1000 |
| = | 1200 | + | 0 | + | X | × | 20 33 | + | 35000 27 |
| = | 67400 27 | + | 20 33 | X |
67400 27 | + | 20 33 | X | = | 3 | ( | 550 | + | X | ) |
| 方程右边 = | 3 | × | 550 | + | 3 | X |
| = | 1650 | + | 3 | X |
67400 27 | + | 20 33 | X | = | 1650 | + | 3 | X |
20 33 | X | − | 3 | X | = | 1650 | − | 67400 27 |
| - | 79 33 | X | = | 1650 | − | 67400 27 |
| - | 79 33 | X | = | - | 22850 27 |
22850 27 | = | 79 33 | X |
79 33 | X | = | 22850 27 |
| X | = | 22850 27 | ÷ | 79 33 |
| = | 22850 27 | × | 33 79 |
| = | 22850 9 | × | 11 79 |
| X | = | 251350 711 |
| X | = | 353.516174 |