Задание 1. Выполни умножение:

a) \(\frac{5}{6} \cdot \frac{3}{20} = \frac{5 \cdot 3}{6 \cdot 20} = \frac{15}{120} = \frac{1}{8}\) б) \(\frac{3}{7} \cdot \frac{6}{11} = \frac{3 \cdot 6}{7 \cdot 11} = \frac{18}{77}\) в) \(\frac{10}{11} \cdot \frac{11}{26} = \frac{10 \cdot 11}{11 \cdot 26} = \frac{10}{26} = \frac{5}{13}\) г) \(\frac{3}{7} \cdot \frac{14}{15} = \frac{3 \cdot 14}{7 \cdot 15} = \frac{42}{105} = \frac{2}{5}\) д) \(\frac{24}{65} \cdot \frac{39}{40} = \frac{24 \cdot 39}{65 \cdot 40} = \frac{936}{2600} = \frac{58.5}{162.5} = \frac{18}{65}\) е) \(4 \cdot \frac{4}{21} = \frac{4 \cdot 4}{21} = \frac{16}{21}\) ж) \(\frac{7}{18} \cdot 6 = \frac{7 \cdot 6}{18} = \frac{42}{18} = \frac{7}{3} = 2\frac{1}{3}\) з) \(\frac{5}{14} \cdot 28 = \frac{5 \cdot 28}{14} = \frac{140}{14} = 10\) и) \(2\frac{1}{7} \cdot 1\frac{1}{5} = \frac{15}{7} \cdot \frac{6}{5} = \frac{15 \cdot 6}{7 \cdot 5} = \frac{90}{35} = \frac{18}{7} = 2\frac{4}{7}\) к) \(3\frac{1}{9} \cdot 21 = \frac{28}{9} \cdot 21 = \frac{28 \cdot 21}{9} = \frac{588}{9} = \frac{196}{3} = 65\frac{1}{3}\) л) \(2\frac{2}{15} \cdot 1\frac{9}{16} = \frac{32}{15} \cdot \frac{25}{16} = \frac{32 \cdot 25}{15 \cdot 16} = \frac{800}{240} = \frac{10}{3} = 3\frac{1}{3}\) м) \(1\frac{1}{7} \cdot 3\frac{1}{2} = \frac{8}{7} \cdot \frac{7}{2} = \frac{8 \cdot 7}{7 \cdot 2} = \frac{56}{14} = 4\)