3) (6 3/4 - 5 1/8 : 1 9/32) : 2 1/5;

3) \((6\frac{3}{4} - 5\frac{1}{8} : 1\frac{9}{32}) : 2\frac{1}{5} = (\frac{27}{4} - \frac{41}{8} : \frac{41}{32}) : \frac{11}{5} = (\frac{27}{4} - \frac{41}{8} \cdot \frac{32}{41}) : \frac{11}{5} = (\frac{27}{4} - \frac{32}{8}) : \frac{11}{5} = (\frac{27}{4} - 4) : \frac{11}{5} = (\frac{27}{4} - \frac{16}{4}) : \frac{11}{5} = \frac{11}{4} : \frac{11}{5} = \frac{11}{4} \cdot \frac{5}{11} = \frac{5}{4} = 1\frac{1}{4}\)

Ответ: 1 1/4