a) \(\frac{3}{7} \cdot \frac{5}{11} = \frac{3 \cdot 5}{7 \cdot 11} = \frac{15}{77}\)
б) \(\frac{6}{25} \cdot \frac{5}{18} = \frac{6 \cdot 5}{25 \cdot 18} = \frac{30}{450} = \frac{1}{15}\)
в) \(3\frac{3}{5} \cdot 1\frac{1}{9} = \frac{3 \cdot 5 + 3}{5} \cdot \frac{1 \cdot 9 + 1}{9} = \frac{18}{5} \cdot \frac{10}{9} = \frac{18 \cdot 10}{5 \cdot 9} = \frac{180}{45} = 4\)
г) \(1\frac{1}{7} \cdot 14 = \frac{1 \cdot 7 + 1}{7} \cdot 14 = \frac{8}{7} \cdot 14 = \frac{8 \cdot 14}{7} = \frac{112}{7} = 16\)
д) \(\frac{5}{9} : \frac{10}{27} = \frac{5}{9} \cdot \frac{27}{10} = \frac{5 \cdot 27}{9 \cdot 10} = \frac{135}{90} = \frac{3}{2} = 1\frac{1}{2}\)
e) \(\frac{12}{13} : 6 = \frac{12}{13} \cdot \frac{1}{6} = \frac{12 \cdot 1}{13 \cdot 6} = \frac{12}{78} = \frac{2}{13}\)
Ответ: а) \(\frac{15}{77}\); б) \(\frac{1}{15}\); в) 4; г) 16; д) \(1\frac{1}{2}\); e) \(\frac{2}{13}\)