| - | 123 | = | - | 23 125 | × | 1359 | + | b |
| 方程右边 = | - | 31257 125 | + | b |
| - | 123 | = | - | 31257 125 | + | b |
| - | b | = | - | 31257 125 | + | 123 |
| - | b | = | - | 15882 125 |
15882 125 | = | b |
| b | = | 15882 125 |
| - | 210 | = | - | 21 200 | × | 1404 | + | b |
| 方程右边 = | - | 7371 50 | + | b |
| - | 210 | = | - | 7371 50 | + | b |
| - | b | = | - | 7371 50 | + | 210 |
| - | b | = | 3129 50 |
| - | 3129 50 | = | b |
| b | = | - | 3129 50 |