1. Вычислите: а) \(\frac{3}{4}\cdot\frac{5}{7}\); б) \(\frac{4}{11}\cdot\frac{3}{4}\); в) \(\frac{5}{7}\cdot\frac{14}{19}\); д) \(\frac{4}{5}:\frac{3}{7}\); е) \(\frac{15}{8}:\frac{5}{4}\); ж) \(\frac{4}{9}:2\).

1. а) \(\frac{3}{4}\cdot\frac{5}{7}=\frac{15}{28}\).
2. б) \(\frac{4}{11}\cdot\frac{3}{4}=\frac{3}{11}\).
3. в) \(\frac{5}{7}\cdot\frac{14}{19}=\frac{10}{19}\).
4. д) \(\frac{4}{5}:\frac{3}{7}=\frac{4}{5}\cdot\frac{7}{3}=\frac{28}{15}\).
5. е) \(\frac{15}{8}:\frac{5}{4}=\frac{15}{8}\cdot\frac{4}{5}=\frac{3}{2}\).
6. ж) \(\frac{4}{9}:2=\frac{4}{9}\cdot\frac{1}{2}=\frac{2}{9}\).

Ответ: а) \(\frac{15}{28}\); б) \(\frac{3}{11}\); в) \(\frac{10}{19}\); д) \(\frac{28}{15}\); е) \(\frac{3}{2}\); ж) \(\frac{2}{9}\).