Сократите дроби: 3/6; 8/16; 8/12; 42n/49n.

\( \frac{3}{6} = \frac{1}{2} \), \( \frac{8}{16} = \frac{1}{2} \), \( \frac{8}{12} = \frac{2}{3} \), \( \frac{42n}{49n} = \frac{6}{7} \).