Ответ:

1)

a)  [tex]\frac{3}{7}*\frac{4}{5} = \frac{12}{35} \\[/tex]

б) [tex]\frac{5}{9} * \frac{2}{5} = \frac{2}{9}[/tex]

в)[tex]\frac{6}{7} * \frac{21}{22} = \frac{3*3}{11} = \frac{9}{11}[/tex]

г)[tex](\frac{3}{4})^3 = \frac{3*3*3}{4*4*4} = \frac{27}{64}[/tex]

д)[tex]\frac{3}{5} : \frac{4}{7} = \frac{3}{5} * \frac{7}{4} = \frac{21}{20} = 1\frac{1}{20} = 1.05[/tex]

е)[tex]\frac{25}{24} : \frac{15}{16} = \frac{25}{24} * \frac{16}{15} = \frac{5*5*4*4}{4*6*5*3} = \frac{10}{9} = 1\frac{1}{9}[/tex]

ж)[tex]\frac{6}{7} : 3 = \frac{6}{21} = \frac{2}{7}[/tex]

з) [tex]8:\frac{4}{5} = 8*\frac{5}{4} =2*5 = 10[/tex]

2)

а)

[tex]\frac{4}{5}*(\frac{15}{16}:\frac{3}{4}) = \frac{4}{5}*(\frac{15}{16}*\frac{4}{3}) = \frac{4}{5}*\frac{5}{4} = 1[/tex]

б) [tex]\frac{15}{23}: \frac{5}{6} *\frac{23}{24} = \frac{15}{23}* \frac{6}{5} *\frac{23}{24} = \frac{5*3*6*23}{23*5*6*4} = \frac{3}{4} = 0.75[/tex]

в) [tex]\frac{3}{4} *\frac{4}{5}* \frac{5}{6} *\frac{6}{7} = \frac{3*4*5*6}{4*5*6*7} = \frac{3}{7}[/tex]