\(\overline{2ab1}=13\times\overline{c2d}\)
\(0\le ab\le99\)\(\Rightarrow\overline{c2d}\le230\Rightarrow\orbr{\begin{cases}c=1\left(l\right)\\c=2\left(tm\right)\end{cases}}\)
\(\Rightarrow\overline{2ab1}=13\cdot\overline{22d}\)
d | \(13\cdot\overline{22d}\) | \(\overline{2ab1}\Rightarrow\overline{ab}\) |
1 | 2873 | L |
2 | 2886 | L |
3 | 2899 | L |
4 | 2912 | L |
5 | 2925 | L |
6 | 2938 | L |
7 | 2951 | 2951 nên ab=95 |
8 | 2964 | L |
9 | 2977 | L |
Vậy số a=9 b=5 c=2 d=7