Ответ:

[tex]\displaystyle \frac{6}{49}[/tex]

Пошаговое объяснение:

[tex]\displaystyle \frac{5\frac{1}{7}*\frac{3}{5} }{12\frac{1}{4}:1\frac{3}{4} } =\frac{\frac{36}{7}*\frac{3}{5}:\frac{18}{5} }{\frac{49}{4}:\frac{7}{4} } =\frac{\frac{36}{7}*\frac{3}{5}*\frac{5}{18} }{\frac{49}{4}*\frac{4}{7} } = \frac{\frac{2}{7}*3 }{7} = \frac{\frac{6}{7} }{7} = \frac{6}{49}[/tex]