$$(3,4-5)\cdot\left(\frac{31}{48}+\frac{7}{2}\right)=-1,6\cdot\left(\frac{31}{48}+\frac{168}{48}\right)=-1,6\cdot\frac{199}{48}=-\frac{16}{10}\cdot\frac{199}{48}=-\frac{1}{10}\cdot\frac{199}{3}=-\frac{199}{30}=-6\frac{19}{30}$$
Ответ: $$-6\frac{19}{30}$$