\[\boxed{\mathbf{3.22}}\]
\[\frac{3}{17} \rightarrow на\ 2:\]
\[\frac{3}{17 - 2} = \frac{3}{15} = \frac{1}{5}.\]
\[\frac{6}{32} \rightarrow на\ 2:\]
\[\frac{6}{32 - 2} = \frac{6}{30} = \frac{1}{5}.\]
\[\frac{7}{55} \rightarrow на\ 20:\]
\[\frac{7}{55 - 20} = \frac{7}{35} = \frac{1}{5}.\]
\[\frac{2}{13} \rightarrow на\ 3:\]
\[\frac{2}{13 - 3} = \frac{2}{10} = \frac{1}{5}.\]