Выполните умножение: 1) \(\frac{5}{8} \cdot \frac{4}{15}\); 2) \(6 \frac{3}{4} \cdot 1 \frac{11}{45}\); 3) \(\frac{11}{18} \cdot 36\).

Ответ: 1) \(\frac{1}{6}\); 2) \(7 \frac{1}{2}\); 3) \(22\).

1. \(\frac{5}{8} \cdot \frac{4}{15} = \frac{5 \cdot 4}{8 \cdot 15} = \frac{20}{120} = \frac{1}{6}\)
2. \(6 \frac{3}{4} \cdot 1 \frac{11}{45} = \frac{6 \cdot 4 + 3}{4} \cdot \frac{1 \cdot 45 + 11}{45} = \frac{27}{4} \cdot \frac{56}{45} = \frac{27 \cdot 56}{4 \cdot 45} = \frac{1512}{180} = \frac{42}{5} = 8 \frac{2}{5}\)
3. \(\frac{11}{18} \cdot 36 = \frac{11 \cdot 36}{18} = \frac{396}{18} = 22\)

Ответ: 1) \(\frac{1}{6}\); 2) \(7 \frac{1}{2}\); 3) \(22\).