- \(\frac{7}{15}:\frac{14}{25}=\frac{7}{15}\cdot\frac{25}{14}=\frac{5}{6}\).
- \(\frac{8}{13}:4=\frac{8}{13}\cdot\frac{1}{4}=\frac{2}{13}\).
- \(9:\frac{27}{28}=9\cdot\frac{28}{27}=\frac{28}{3}=9\frac{1}{3}\).
- \(2\frac{2}{9}:1\frac{7}{9}=\frac{20}{9}:\frac{16}{9}=\frac{5}{4}=1\frac{1}{4}\).
Ответ: 1) \(\frac{5}{6}\); 2) \(\frac{2}{13}\); 3) \(9\frac{1}{3}\); 4) \(1\frac{1}{4}\).