14. Вычислите: $$\frac{5}{4} + (-7\frac{3}{4} + \frac{7}{4} \cdot 2\frac{2}{7}) : \frac{5}{9}$$

Решим пример по действиям: 1) $$2\frac{2}{7} = \frac{2 \cdot 7 + 2}{7} = \frac{16}{7}$$ 2) $$\frac{7}{4} \cdot \frac{16}{7} = \frac{7 \cdot 16}{4 \cdot 7} = \frac{16}{4} = 4$$ 3) $$-7\frac{3}{4} = -\frac{7 \cdot 4 + 3}{4} = -\frac{31}{4}$$ 4) $$-\frac{31}{4} + 4 = -\frac{31}{4} + \frac{16}{4} = \frac{-31 + 16}{4} = -\frac{15}{4}$$ 5) $$\frac{5}{4} + (-\frac{15}{4}) : \frac{5}{9} = \frac{5}{4} + (-\frac{15}{4} \cdot \frac{9}{5}) = \frac{5}{4} + (-\frac{15 \cdot 9}{4 \cdot 5}) = \frac{5}{4} + (-\frac{3 \cdot 9}{4}) = \frac{5}{4} - \frac{27}{4} = \frac{5 - 27}{4} = \frac{-22}{4} = -\frac{11}{2} = -5\frac{1}{2}$$ Ответ: -5.5