5.542 Выполните действия: a) \(\frac{3}{8} \div \frac{3}{4} \cdot \frac{2}{3}\); б) \(\frac{10}{7} \div \frac{3}{4} \div \frac{4}{14}\); в) \(\frac{121}{284} \div \frac{11}{12}\); г) \(\frac{8}{15} \div \frac{8}{5} \div \frac{3}{16}\)?

a) \(\frac{3}{8} \div \frac{3}{4} \cdot \frac{2}{3} = \frac{3}{8} \cdot \frac{4}{3} \cdot \frac{2}{3} = \frac{3 \cdot 4 \cdot 2}{8 \cdot 3 \cdot 3} = \frac{24}{72} = \frac{1}{3}\) б) \(\frac{10}{7} \div \frac{3}{4} \div \frac{4}{14} = \frac{10}{7} \cdot \frac{4}{3} \cdot \frac{14}{4} = \frac{10 \cdot 4 \cdot 14}{7 \cdot 3 \cdot 4} = \frac{560}{84} = \frac{20}{3} = 6\frac{2}{3}\) в) \(\frac{121}{284} \div \frac{11}{12} = \frac{121}{284} \cdot \frac{12}{11} = \frac{121 \cdot 12}{284 \cdot 11} = \frac{11 \cdot 12}{284} = \frac{132}{284} = \frac{33}{71}\) г) \(\frac{8}{15} \div \frac{8}{5} \div \frac{3}{16} = \frac{8}{15} \cdot \frac{5}{8} \cdot \frac{16}{3} = \frac{8 \cdot 5 \cdot 16}{15 \cdot 8 \cdot 3} = \frac{5 \cdot 16}{15 \cdot 3} = \frac{80}{45} = \frac{16}{9} = 1\frac{7}{9}\)