| ( | 1200 | × | 12 | ) | ÷ | 3 100 | × | 88 | x | + | 88 | x | = | 19 500 |
| 方程左边 = | ( | 1200 | × | 12 | ) | × | 8800 3 | x | + | 88 | x |
| ( | 1200 | × | 12 | ) | × | 8800 3 | x | + | 88 | x | = | 19 500 |
| 方程左边 = | 1200 | × | 12 | × | 8800 3 | x | + | 88 | x |
| = | 42240000 | x | + | 88 | x |
| = | 42240088 | x |
| 42240088 | x | = | 19 500 |
| x | = | 19 500 | ÷ | 42240088 |
| = | 19 500 | × | 1 42240088 |
| x | = | 19 21120044000 |