3. Вычислите: a) $$\frac{7}{9}:(-\frac{1}{36})$$ b) $$\frac{24}{49}: \frac{6}{7} + \frac{1}{14}$$

a) $$\frac{7}{9}:(-\frac{1}{36}) = \frac{7}{9} * (-36) = -28$$ б) $$\frac{24}{49}: \frac{6}{7} + \frac{1}{14} = \frac{24}{49} * \frac{7}{6} + \frac{1}{14} = \frac{4}{7} + \frac{1}{14} = \frac{8}{14} + \frac{1}{14} = \frac{9}{14}$$ Ответ: a) -28 б) $$\frac{9}{14}$$