Ответ:
\[\frac{2}{15}\ :x = \frac{4}{25}\]
\[x = \frac{2}{15}\ :\frac{4}{25}\]
\[x = \frac{2}{15} \cdot \frac{25}{4}\]
\[x = \frac{5}{6}.\]
\[\frac{2}{15}\ :x = \frac{4}{25}\]
\[x = \frac{2}{15}\ :\frac{4}{25}\]
\[x = \frac{2}{15} \cdot \frac{25}{4}\]
\[x = \frac{5}{6}.\]