3)70-2-

3) $$7\frac{3}{8}-2\frac{1}{8}=\frac{59}{8}-\frac{17}{8}=\frac{42}{8}=\frac{21}{4}=5\frac{2}{8}=5\frac{1}{4}$$

Ответ:$$5\frac{1}{4}$$