1. Вычислите: а) 2/3 · 1 2/7; б) 3 1/8 · 2; в) 1 1/7 · 1 3/4; г) 5/6 : 2 2/9; д) 3 3/5 : 9; е) 7 3/5 : 1 9/10.

а) \(\frac{2}{3}\cdot1\frac{2}{7}=\frac{2}{3}\cdot\frac{9}{7}=\frac{6}{7}\).

б) \(3\frac{1}{8}\cdot2=\frac{25}{8}\cdot2=\frac{25}{4}=6\frac{1}{4}\).

в) \(1\frac{1}{7}\cdot1\frac{3}{4}=\frac{8}{7}\cdot\frac{7}{4}=2\).

г) \(\frac{5}{6}:2\frac{2}{9}=\frac{5}{6}:\frac{20}{9}=\frac{5}{6}\cdot\frac{9}{20}=\frac{3}{8}\).

д) \(3\frac{3}{5}:9=\frac{18}{5}:9=\frac{18}{5}\cdot\frac{1}{9}=\frac{2}{5}\).

е) \(7\frac{3}{5}:1\frac{9}{10}=\frac{38}{5}:\frac{19}{10}=\frac{38}{5}\cdot\frac{10}{19}=4\).

Ответ: а) \(\frac{6}{7}\); б) \(6\frac{1}{4}\); в) \(2\); г) \(\frac{3}{8}\); д) \(\frac{2}{5}\); е) \(4\).