Выполни умножение или деление дробей: 5/12 * 4

- $\frac{5}{12} \cdot 4 = \frac{5 \cdot 4}{12} = \frac{20}{12} = \frac{5}{3}$ - $\frac{3}{7} \cdot 49 = \frac{3 \cdot 49}{7} = \frac{3 \cdot 7 \cdot 7}{7} = 3 \cdot 7 = 21$ - $\frac{5}{8} : 25 = \frac{5}{8} \cdot \frac{1}{25} = \frac{5}{8 \cdot 25} = \frac{5}{8 \cdot 5 \cdot 5} = \frac{1}{8 \cdot 5} = \frac{1}{40}$ - $\frac{3}{14} : 9 = \frac{3}{14} \cdot \frac{1}{9} = \frac{3}{14 \cdot 9} = \frac{3}{14 \cdot 3 \cdot 3} = \frac{1}{14 \cdot 3} = \frac{1}{42}$ - $5 : \frac{15}{19} = 5 \cdot \frac{19}{15} = \frac{5 \cdot 19}{15} = \frac{5 \cdot 19}{5 \cdot 3} = \frac{19}{3}$ - $4 : \frac{16}{25} = 4 \cdot \frac{25}{16} = \frac{4 \cdot 25}{16} = \frac{4 \cdot 25}{4 \cdot 4} = \frac{25}{4}$ - $\frac{4}{5} \cdot 15 = \frac{4 \cdot 15}{5} = \frac{4 \cdot 5 \cdot 3}{5} = 4 \cdot 3 = 12$ - $\frac{2}{9} \cdot 81 = \frac{2 \cdot 81}{9} = \frac{2 \cdot 9 \cdot 9}{9} = 2 \cdot 9 = 18$ - $\frac{4}{7} : 16 = \frac{4}{7} \cdot \frac{1}{16} = \frac{4}{7 \cdot 16} = \frac{4}{7 \cdot 4 \cdot 4} = \frac{1}{7 \cdot 4} = \frac{1}{28}$ - $\frac{5}{16} : 25 = \frac{5}{16} \cdot \frac{1}{25} = \frac{5}{16 \cdot 25} = \frac{5}{16 \cdot 5 \cdot 5} = \frac{1}{16 \cdot 5} = \frac{1}{80}$ - $6 : \frac{12}{17} = 6 \cdot \frac{17}{12} = \frac{6 \cdot 17}{12} = \frac{6 \cdot 17}{6 \cdot 2} = \frac{17}{2}$ - $4 : \frac{16}{41} = 4 \cdot \frac{41}{16} = \frac{4 \cdot 41}{16} = \frac{4 \cdot 41}{4 \cdot 4} = \frac{41}{4}$