Ответ:

а) \(\frac{12}{7}\cdot\frac{14}{27}=\frac{2\cdot14}{7\cdot9}=\frac{4}{9}\).

б) \(\frac{20}{23}\cdot\frac{73}{48}\cdot\frac{46}{73}=\frac{20\cdot2}{48}=\frac{5}{6}\).

в) \(4\frac{1}{2}\cdot\frac{14}{15}=\frac{9}{2}\cdot\frac{14}{15}=\frac{21}{5}=4\frac{1}{5}\).

г) \(3\frac{3}{5}\cdot5\frac{5}{8}=\frac{18}{5}\cdot\frac{45}{8}=\frac{81}{4}=20\frac{1}{4}\).

д) \(1\frac{1}{24}\cdot11\frac{1}{5}=\frac{25}{24}\cdot\frac{56}{5}=\frac{35}{3}=11\frac{2}{3}\).

е) \(12\frac{4}{5}\cdot3\frac{1}{8}=\frac{64}{5}\cdot\frac{25}{8}=40\).

Ответ: а) \(\frac{4}{9}\); б) \(\frac{5}{6}\); в) \(4\frac{1}{5}\); г) \(20\frac{1}{4}\); д) \(11\frac{2}{3}\); е) \(40\).