Решение:
a) \(5 \frac{1}{3} \cdot 2 \frac{1}{4} : \frac{4}{5} = \frac{16}{3} \cdot \frac{9}{4} : \frac{4}{5} = \frac{16}{3} \cdot \frac{9}{4} \cdot \frac{5}{4} = \frac{4}{1} \cdot \frac{3}{1} \cdot \frac{5}{4} = \frac{12 \cdot 5}{4} = \frac{60}{4} = 15\)
в) \(2 \frac{2}{5} : (3 \frac{2}{5} - 1 \frac{11}{15}) = \frac{12}{5} : (3 \frac{6}{15} - 1 \frac{11}{15}) = \frac{12}{5} : (2 \frac{21}{15} - 1 \frac{11}{15}) = \frac{12}{5} : 1 \frac{10}{15} = \frac{12}{5} : 1 \frac{2}{3} = \frac{12}{5} : \frac{5}{3} = \frac{12}{5} \cdot \frac{3}{5} = \frac{36}{25} = 1 \frac{11}{25}\)
Ответ: а) 15; в) \(1 \frac{11}{25}\)