375. Выполнить указанные действия: 1):7; 9 11 3)5; 2 4 4) 663 2)5:9; 11 1236 3) 3:4½: (7:읍). 80; 376.1) 6금: 30:93:27; 2) 1/6 : (2/41:50); 5 5) 143 8 25.

Задание 375

1. \[\frac{5}{6} : 7 = \frac{5}{6} \cdot \frac{1}{7} = \frac{5}{42}\]
2. \[5 : \frac{6}{7} = 5 \cdot \frac{7}{6} = \frac{35}{6} = 5\frac{5}{6}\]
3. \[\frac{1 \frac{1}{2}}{5} = \frac{\frac{3}{2}}{5} = \frac{3}{2} : 5 = \frac{3}{2} \cdot \frac{1}{5} = \frac{3}{10}\]
4. \[\frac{66\frac{2}{3}}{80} = \frac{\frac{200}{3}}{80} = \frac{200}{3} : 80 = \frac{200}{3} \cdot \frac{1}{80} = \frac{200}{240} = \frac{5}{6}\]
5. \[\frac{14\frac{3}{8}}{25} = \frac{\frac{115}{8}}{25} = \frac{115}{8} : 25 = \frac{115}{8} \cdot \frac{1}{25} = \frac{115}{200} = \frac{23}{40}\]

Задание 376

1. \[6\frac{11}{12} : \frac{15}{36} : 9\frac{3}{5} : 27\frac{2}{3} = \frac{83}{12} : \frac{15}{36} : \frac{48}{5} : \frac{83}{3} = \frac{83}{12} \cdot \frac{36}{15} \cdot \frac{5}{48} \cdot \frac{3}{83} = \frac{83 \cdot 36 \cdot 5 \cdot 3}{12 \cdot 15 \cdot 48 \cdot 83} = \frac{1}{8}\]
2. \[1\frac{1}{6} : (2\frac{1}{4} : 5\frac{2}{5}) = \frac{7}{6} : (\frac{9}{4} : \frac{27}{5}) = \frac{7}{6} : (\frac{9}{4} \cdot \frac{5}{27}) = \frac{7}{6} : \frac{5}{12} = \frac{7}{6} \cdot \frac{12}{5} = \frac{7 \cdot 12}{6 \cdot 5} = \frac{14}{5} = 2\frac{4}{5}\]
3. \[3\frac{1}{9} : 4\frac{1}{2} : (7\frac{3}{4} : \frac{9}{14}) = \frac{28}{9} : \frac{9}{2} : (\frac{31}{4} : \frac{9}{14}) = \frac{28}{9} : \frac{9}{2} : (\frac{31}{4} \cdot \frac{14}{9}) = \frac{28}{9} : \frac{9}{2} : \frac{217}{18} = \frac{28}{9} \cdot \frac{2}{9} \cdot \frac{18}{217} = \frac{28 \cdot 2 \cdot 18}{9 \cdot 9 \cdot 217} = \frac{112}{976} = \frac{112}{981} \approx 0.11417\]