1. Выполните умножение: 1) \(\frac{4}{5}\cdot \frac{15}{16}\); 2) \(3\frac{1}{3}\cdot 1\frac{2}{25}\); 3) \(\frac{5}{13}\cdot 39.\)

1) \(\frac{4}{5}\cdot \frac{15}{16} = \frac{4\cdot 15}{5\cdot 16} = \frac{4\cdot 3\cdot 5}{5\cdot 4 \cdot 4} = \frac{3}{4}\)

2) \(3\frac{1}{3}\cdot 1\frac{2}{25} = \frac{10}{3}\cdot \frac{27}{25} = \frac{10\cdot 27}{3\cdot 25} = \frac{5\cdot 2 \cdot 3 \cdot 9}{3\cdot 5 \cdot 5} = \frac{2\cdot 9}{5} = \frac{18}{5} = 3\frac{3}{5}\)

3) \(\frac{5}{13}\cdot 39 = \frac{5\cdot 39}{13} = \frac{5\cdot 3\cdot 13}{13} = 5\cdot 3 = 15\)

Ответ: 1) \(\frac{3}{4}\); 2) \(3\frac{3}{5}\); 3) \(15\)