5.542 Выполните действия: а) 3/8 : 3/4 * 2/3; б) 10/7 * 3/4 : 5/14; в) 9/8 : 5/8 : 3/10

$$\frac{3}{8} : \frac{3}{4} \cdot \frac{2}{3} = \frac{3}{8} \cdot \frac{4}{3} \cdot \frac{2}{3} = \frac{24}{72} = \frac{1}{3}$$

$$\frac{10}{7} \cdot \frac{3}{4} : \frac{5}{14} = \frac{30}{28} : \frac{5}{14} = \frac{15}{14} \cdot \frac{14}{5} = 3$$

$$\frac{9}{8} : \frac{5}{8} : \frac{3}{10} = \frac{9}{8} \cdot \frac{8}{5} : \frac{3}{10} = \frac{9}{5} : \frac{3}{10} = \frac{9}{5} \cdot \frac{10}{3} = 6$$