Решение:
а) \(3\frac{1}{5} : (16 : 1\frac{1}{3}) = \frac{16}{5} : (16 : \frac{4}{3}) = \frac{16}{5} : (16 \cdot \frac{3}{4}) = \frac{16}{5} : 12 = \frac{16}{5} \cdot \frac{1}{12} = \frac{4}{5} \cdot \frac{1}{3} = \frac{4}{15}\)
б) \((1 - \frac{2}{5}) : (2\frac{6}{11} : \frac{56}{121}) = \frac{3}{5} : (\frac{28}{11} : \frac{56}{121}) = \frac{3}{5} : (\frac{28}{11} \cdot \frac{121}{56}) = \frac{3}{5} : (\frac{1}{1} \cdot \frac{11}{2}) = \frac{3}{5} : \frac{11}{2} = \frac{3}{5} \cdot \frac{2}{11} = \frac{6}{55}\)
Ответ:
а) \(\frac{4}{15}\)
б) \(\frac{6}{55}\)