1) $$\frac{5}{8} \cdot \frac{4}{15} = \frac{5 \cdot 4}{8 \cdot 15} = \frac{20}{120} = \frac{1}{6}$$
2) $$5 \frac{3}{5} \cdot \frac{14}{21} = \frac{5 \cdot 5 + 3}{5} \cdot \frac{14}{21} = \frac{28}{5} \cdot \frac{14}{21} = \frac{28 \cdot 14}{5 \cdot 21} = \frac{4 \cdot 2}{5 \cdot 3} = \frac{8}{15}$$
3) $$\frac{13}{16} \cdot 32 = \frac{13 \cdot 32}{16} = \frac{13 \cdot 2}{1} = 26$$
Ответ: 1) 1/6; 2) 8/15; 3) 26