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Решите задачу:

$( \frac{1}{5} \times \frac{3}{4} ) \times \frac{2}{3} = \frac{3}{20 } \times \frac{2}{3} = \frac{1}{10} = 0.1$
$\frac{2}{9} \times ( \frac{3}{10} \times \frac{7}{8} ) = \frac{2}{9} \times \frac{21}{80} = \frac{21}{360} = \frac{7}{120}$
$( \frac{15}{19} \times \frac{7}{9} ) \times \frac{5}{7} = \frac{105}{171} \times \frac{5}{7} = \frac{525}{1197} = \frac{175}{399} = \frac{25}{57}$
$( \frac{10}{13} \times \frac{11}{12} ) \times ( \frac{12}{55} \times \frac{13}{20} ) = \frac{55}{78} \times \frac{78}{550} = \frac{1}{ 10} = 0.1$