11. Решите уравнения: 1) \(\frac{7}{12}y=1\frac{1}{6}\); 2) \(\frac{8}{15}x=3\frac{1}{5}\); 3) \(\frac{5}{14}b=2\frac{1}{7}\); 4) \(\frac{9}{16}a=5\frac{1}{4}\).

1. \(y=1\frac{1}{6}:\frac{7}{12}=\frac{7}{6}\cdot\frac{12}{7}=2\).
2. \(x=3\frac{1}{5}:\frac{8}{15}=\frac{16}{5}\cdot\frac{15}{8}=6\).
3. \(b=2\frac{1}{7}:\frac{5}{14}=\frac{15}{7}\cdot\frac{14}{5}=6\).
4. \(a=5\frac{1}{4}:\frac{9}{16}=\frac{21}{4}\cdot\frac{16}{9}=\frac{28}{3}=9\frac{1}{3}\).

Ответ: 1) \(y=2\); 2) \(x=6\); 3) \(b=6\); 4) \(a=9\frac{1}{3}\).