\[\boxed{\mathbf{380}\mathbf{.}}\]
\[\frac{3}{13} < x < \frac{4}{13}\]
\[\frac{12}{54} < x < \frac{16}{52}\]
\[\frac{13}{52} = \frac{1}{4};\ \frac{14}{52} = \frac{7}{26};\ \frac{15}{52}.\]