Выполни сложение или вычитание дробей: 1/2 + 3/8

- $\frac{1}{2} + \frac{3}{8} = \frac{4}{8} + \frac{3}{8} = \frac{7}{8}$ - $\frac{2}{7} + \frac{5}{14} = \frac{4}{14} + \frac{5}{14} = \frac{9}{14}$ - $\frac{3}{5} + \frac{4}{15} = \frac{9}{15} + \frac{4}{15} = \frac{13}{15}$ - $\frac{1}{8} + \frac{3}{16} = \frac{2}{16} + \frac{3}{16} = \frac{5}{16}$ - $\frac{2}{9} + \frac{5}{18} = \frac{4}{18} + \frac{5}{18} = \frac{9}{18} = \frac{1}{2}$ - $\frac{17}{33} - \frac{5}{22} = \frac{34}{66} - \frac{15}{66} = \frac{19}{66}$ - $\frac{27}{76} - 0 = \frac{27}{76}$ - $\frac{9}{20} + \frac{5}{8} = \frac{18}{40} + \frac{25}{40} = \frac{43}{40} = 1\frac{3}{40}$ - $\frac{2}{7} + \frac{13}{28} = \frac{8}{28} + \frac{13}{28} = \frac{21}{28} = \frac{3}{4}$ - $\frac{5}{13} - \frac{14}{39} = \frac{15}{39} - \frac{14}{39} = \frac{1}{39}$