| ( | 666000 | − | 1863 4000 | X | ) | ÷ | ( | 99 20 | X | ) | = | 3517 100000 |
| 方程两边同时乘以: | ( | 99 20 | X | ) |
| ( | 666000 | − | 1863 4000 | X | ) | = | 3517 100000 | ( | 99 20 | X | ) |
| 666000 | − | 1863 4000 | X | = | 3517 100000 | ( | 99 20 | X | ) |
| 666000 | − | 1863 4000 | X | = | 3517 100000 | × | 99 20 | X |
| 666000 | − | 1863 4000 | X | = | 348183 2000000 | X |
| - | 1863 4000 | X | − | 348183 2000000 | X | = | - | 666000 |
| - | 1279683 2000000 | X | = | - | 666000 |
| 666000 | = | 1279683 2000000 | X |
1279683 2000000 | X | = | 666000 |
| X | = | 666000 | ÷ | 1279683 2000000 |
| = | 666000 | × | 2000000 1279683 |
| = | 74000 | × | 2000000 142187 |
| X | = | 148000000000 142187 |