Выполни деление дробей в задании под буквой а)

- a) $\frac{3}{8} : \frac{2}{3} = \frac{3}{8} \cdot \frac{3}{2} = \frac{3 \cdot 3}{8 \cdot 2} = \frac{9}{16}$ - б) $\frac{4}{7} : \frac{4}{9} = \frac{4}{7} \cdot \frac{9}{4} = \frac{4 \cdot 9}{7 \cdot 4} = \frac{9}{7} = 1\frac{2}{7}$ - в) $11\frac{2}{5} : 3\frac{4}{5} = \frac{11 \cdot 5 + 2}{5} : \frac{3 \cdot 5 + 4}{5} = \frac{57}{5} : \frac{19}{5} = \frac{57}{5} \cdot \frac{5}{19} = \frac{57 \cdot 5}{5 \cdot 19} = \frac{57}{19} = 3$ - г) $\frac{16}{17} : 8 = \frac{16}{17} : \frac{8}{1} = \frac{16}{17} \cdot \frac{1}{8} = \frac{16 \cdot 1}{17 \cdot 8} = \frac{2}{17}$ - д) $4\frac{1}{11} : 2\frac{19}{22} = \frac{4 \cdot 11 + 1}{11} : \frac{2 \cdot 22 + 19}{22} = \frac{45}{11} : \frac{63}{22} = \frac{45}{11} \cdot \frac{22}{63} = \frac{45 \cdot 22}{11 \cdot 63} = \frac{10}{7} = 1\frac{3}{7}$ - е) $18 : \frac{9}{14} = \frac{18}{1} : \frac{9}{14} = \frac{18}{1} \cdot \frac{14}{9} = \frac{18 \cdot 14}{1 \cdot 9} = 28$ **Ответы:** - a) $\frac{9}{16}$ - б) $1\frac{2}{7}$ - в) $3$ - г) $\frac{2}{17}$ - д) $1\frac{3}{7}$ - е) $28$