186. Выполните действия: 1) $$\frac{7}{24} + \frac{8}{24}$$; 3) $$\frac{8}{19} + \frac{5}{19} - \frac{4}{19}$$.

1) $$\frac{7}{24} + \frac{8}{24} = \frac{7+8}{24} = \frac{15}{24} = \frac{5}{8}$$.

3) $$\frac{8}{19} + \frac{5}{19} - \frac{4}{19} = \frac{8+5-4}{19} = \frac{9}{19}$$.

Ответ: 1) $$\frac{5}{8}$$; 3) $$\frac{9}{19}$$