Ответ:

а) \(\frac{1}{3}+\frac{3}{6}=\frac{2}{6}+\frac{3}{6}=\frac{5}{6}\).

б) \(\frac{5}{6}-\frac{1}{2}=\frac{5}{6}-\frac{3}{6}=\frac{2}{6}=\frac{1}{3}\).

в) \(\frac{2}{3}+\frac{1}{6}=\frac{4}{6}+\frac{1}{6}=\frac{5}{6}\).

г) \(\frac{3}{8}+\frac{4}{8}=\frac{7}{8}\).

Ответ: а) \(\frac{5}{6}\); б) \(\frac{1}{3}\); в) \(\frac{5}{6}\); г) \(\frac{7}{8}\).