2. Вычислите: а) \frac{14}{15} - \frac{14}{45} : \frac{7}{18}; 6) 14.\frac{3}{56} - \frac{13}{36}; B) \frac{9}{35} : (\frac{7}{24}+\frac{1}{18})

а) \[\frac{14}{15} - \frac{14}{45} : \frac{7}{18} = \frac{14}{15} - \frac{14}{45} \cdot \frac{18}{7} = \frac{14}{15} - \frac{2}{5} \cdot \frac{2}{1} = \frac{14}{15} - \frac{4}{5} = \frac{14}{15} - \frac{12}{15} = \frac{2}{15}\]

б) \[14 \cdot \frac{3}{56} - \frac{13}{36} = \frac{14}{1} \cdot \frac{3}{56} - \frac{13}{36} = \frac{1}{1} \cdot \frac{3}{4} - \frac{13}{36} = \frac{3}{4} - \frac{13}{36} = \frac{27}{36} - \frac{13}{36} = \frac{14}{36} = \frac{7}{18}\]

в) \[\frac{9}{35} : (\frac{7}{24}+\frac{1}{18}) = \frac{9}{35} : (\frac{7 \cdot 3}{24 \cdot 3}+\frac{1 \cdot 4}{18 \cdot 4}) = \frac{9}{35} : (\frac{21}{72}+\frac{4}{72}) = \frac{9}{35} : \frac{25}{72} = \frac{9}{35} \cdot \frac{72}{25} = \frac{648}{875}\]