1. Выполните действия: a) $$1\frac{7}{9}:2\frac{2}{3}$$; б) $$3\frac{3}{5}:2\frac{1}{10}$$; в) $$3\frac{3}{8}:\frac{1}{8}-1\frac{5}{14}\cdot7$$.

a) $$1\frac{7}{9}:2\frac{2}{3} = \frac{16}{9}:\frac{8}{3} = \frac{16}{9}\cdot\frac{3}{8} = \frac{2}{3}$$

б) $$3\frac{3}{5}:2\frac{1}{10} = \frac{18}{5}:\frac{21}{10} = \frac{18}{5}\cdot\frac{10}{21} = \frac{6}{1}\cdot\frac{2}{7} = \frac{12}{7} = 1\frac{5}{7}$$

в) $$3\frac{3}{8}:\frac{1}{8}-1\frac{5}{14}\cdot7 = \frac{27}{8}:\frac{1}{8} - \frac{19}{14}\cdot7 = \frac{27}{8}\cdot\frac{8}{1} - \frac{19}{2}\cdot1 = 27 - \frac{19}{2} = \frac{54-19}{2} = \frac{35}{2} = 17\frac{1}{2}$$