Найдите произведение: 1) \(5 \cdot \frac{3}{26}\) 2) \(\frac{5}{8} \cdot 4\) 3) \(\frac{9}{28} \cdot 56\) 4) \(6\frac{6}{7} \cdot \frac{3}{8}\) 5) \(5\frac{1}{7} \cdot 1\frac{8}{27}\) 6) \(1\frac{8}{9} \cdot 1\frac{1}{8} \cdot 2\frac{2}{3}\)

Решение:

1. \(5 \cdot \frac{3}{26} = \frac{5 \cdot 3}{26} = \frac{15}{26}\)
2. \(\frac{5}{8} \cdot 4 = \frac{5 \cdot 4}{8} = \frac{20}{8} = \frac{5}{2}\)
3. \(\frac{9}{28} \cdot 56 = \frac{9 \cdot 56}{28} = 9 \cdot 2 = 18\)
4. \(6\frac{6}{7} \cdot \frac{3}{8} = \frac{6 €‚ 7 + 6}{7} \cdot \frac{3}{8} = \frac{48}{7} \cdot \frac{3}{8} = \frac{48 \cdot 3}{7 \cdot 8} = \frac{6 \cdot 3}{7} = \frac{18}{7}\)
5. \(5\frac{1}{7} \cdot 1\frac{8}{27} = \frac{5 €‚ 7 + 1}{7} \cdot \frac{1 \u0080‚ 27 + 8}{27} = \frac{36}{7} \cdot \frac{35}{27} = \frac{36 \cdot 35}{7 \cdot 27} = \frac{(4 \cdot 9) \cdot (5 \cdot 7)}{7 \cdot (3 \cdot 9)} = \frac{4 \cdot 5}{3} = \frac{20}{3}\)
6. \(1\frac{8}{9} \cdot 1\frac{1}{8} \cdot 2\frac{2}{3} = \frac{1 €‚ 9 + 8}{9} \cdot \frac{1 \u0080‚ 8 + 1}{8} \cdot \frac{2 \u0080‚ 3 + 2}{3} = \frac{17}{9} \cdot \frac{9}{8} \cdot \frac{8}{3} = \frac{17 \cdot 9 \cdot 8}{9 \cdot 8 \cdot 3} = \frac{17}{3}\)

Ответ: 1) \(\frac{15}{26}\), 2) \(\frac{5}{2}\), 3) \(18\), 4) \(\frac{18}{7}\), 5) \(\frac{20}{3}\), 6) \(\frac{17}{3}\).