№2. Вычислите: a) \(\frac{17}{20} : \frac{34}{30} - \frac{2}{9}\) б) \(\frac{9}{25} \cdot \frac{35}{36} + \frac{1}{6}\)

Решение: a) \(\frac{17}{20} : \frac{34}{30} - \frac{2}{9} = \frac{17}{20} \cdot \frac{30}{34} - \frac{2}{9} = \frac{1}{2} \cdot \frac{3}{2} - \frac{2}{9} = \frac{3}{4} - \frac{2}{9} = \frac{27 - 8}{36} = \frac{19}{36}\) б) \(\frac{9}{25} \cdot \frac{35}{36} + \frac{1}{6} = \frac{1}{5} \cdot \frac{7}{4} + \frac{1}{6} = \frac{7}{20} + \frac{1}{6} = \frac{42 + 20}{120} = \frac{62}{120} = \frac{31}{60}\)