3. Найдите произведение: 1) \(6\frac{6}{7} \cdot \frac{3}{8}\); 2) \(5\frac{1}{7} \cdot 1\frac{8}{27}\); 3) \(2\frac{5}{8} \cdot 2\frac{2}{7}\); 4) \(1\frac{8}{9} \cdot 1\frac{1}{8} \cdot 2\frac{2}{3}\);

1) \(6\frac{6}{7} \cdot \frac{3}{8} = \frac{6 \cdot 7 + 6}{7} \cdot \frac{3}{8} = \frac{48}{7} \cdot \frac{3}{8} = \frac{6}{7} \cdot \frac{3}{1} = \frac{18}{7} = 2\frac{4}{7}\) 2) \(5\frac{1}{7} \cdot 1\frac{8}{27} = \frac{5 \cdot 7 + 1}{7} \cdot \frac{1 \cdot 27 + 8}{27} = \frac{36}{7} \cdot \frac{35}{27} = \frac{4}{1} \cdot \frac{5}{3} = \frac{20}{3} = 6\frac{2}{3}\) 3) \(2\frac{5}{8} \cdot 2\frac{2}{7} = \frac{2 \cdot 8 + 5}{8} \cdot \frac{2 \cdot 7 + 2}{7} = \frac{21}{8} \cdot \frac{16}{7} = \frac{3}{1} \cdot \frac{2}{1} = 6\) 4) \(1\frac{8}{9} \cdot 1\frac{1}{8} \cdot 2\frac{2}{3} = \frac{1 \cdot 9 + 8}{9} \cdot \frac{1 \cdot 8 + 1}{8} \cdot \frac{2 \cdot 3 + 2}{3} = \frac{17}{9} \cdot \frac{9}{8} \cdot \frac{8}{3} = \frac{17}{1} \cdot \frac{1}{1} \cdot \frac{1}{3} = \frac{17}{3} = 5\frac{2}{3}\) Ответ: 1) \(2\frac{4}{7}\); 2) \(6\frac{2}{3}\); 3) 6; 4) \(5\frac{2}{3}\)