\[\boxed{\text{5.329.}}\]
\[\frac{1}{2} = \frac{1 \cdot 7}{2 \cdot 7} = \frac{7}{14}\ \]
\[\frac{1}{7} = \frac{1 \cdot 2}{7 \cdot 2} = \frac{2}{14}\ \]
\[\frac{2}{7} = \frac{2 \cdot 2}{7 \cdot 2} = \frac{4}{14}\]
\[\frac{7}{2} = \frac{7 \cdot 7}{2 \cdot 7} = \frac{49}{14}\ \]