65 5 4 4) 윽 : 특· 음.

$$\frac{6}{7} : \frac{5}{7} \cdot \frac{4}{9} = \frac{6}{7} \cdot \frac{7}{5} \cdot \frac{4}{9} = \frac{6 \cdot 7 \cdot 4}{7 \cdot 5 \cdot 9} = \frac{6 \cdot 4}{5 \cdot 9} = \frac{24}{45} = \frac{8 \cdot 3}{15 \cdot 3} = \frac{8}{15}$$.

Ответ: $$\frac{8}{15}$$