\[\frac{1}{2} = 0.5\] и \[[\frac{5}{8} = 0.625\], значит \[[\frac{1}{2} < \frac{5}{8}\]
\[\frac{5}{8} = 0.625\] и \[[\frac{3}{4} = 0.75\], значит \[[\frac{5}{8} < \frac{3}{4}\]
\[\frac{3}{8} = 0.375\] и \[[\frac{7}{12} = 0.58(3)\], значит \[[\frac{3}{8} < \frac{7}{12}\]
\[\frac{8}{8} = 1\] и \[[\frac{2}{5} = 0.4\], значит \[[\frac{8}{8} > \frac{2}{5}\]
Ответ: \[\frac{1}{2} < \frac{5}{8}; \frac{5}{8} < \frac{3}{4}; \frac{3}{8} < \frac{7}{12}; \frac{8}{8} > \frac{2}{5}\]