2 6 3 7

\[ \frac{2}{3} \div \frac{6}{7} = \frac{2}{3} \cdot \frac{7}{6} = \frac{2 \cdot 7}{3 \cdot 6} = \frac{14}{18} = \frac{7}{9} \]

Ответ: \(\frac{7}{9}\)