\[\boxed{\text{5.393.}}\]
\[\textbf{а)}\ \frac{3}{7} > \frac{7}{28}\]
\[\frac{3}{7} = \frac{12}{28} > \frac{7}{28}\text{.\ }\]
\[\textbf{б)}\ \frac{6}{25} < \frac{3}{5}\]
\[\frac{6}{25} < \frac{3}{5} = \frac{15}{25}.\]
\[\textbf{в)}\ \frac{9}{70} < \frac{7}{10}\]
\[\frac{9}{70} < \frac{7}{10} = \frac{49}{70}\text{.\ }\]
\[\textbf{г)}\ \frac{13}{60} < \frac{5}{12}\ \]
\[\frac{13}{60} < \frac{5}{12} = \frac{25}{60}\text{.\ \ }\]