(5[1] \ [6]-3,25)*[4] \[23]

[latex](5\frac{1}{6}-3,25)\cdot \frac{4}{23}=(5\frac{1}{6}-3\frac{1}{4})\cdot \frac{4}{23}=(\frac{31}{6}-\frac{13}{4})\cdot \frac{4}{23}=\frac{31\cdot 2-13\cdot 3}{12}\cdot \frac{4}{23}=\\\\=\frac{23}{12}\cdot \frac{4}{23}=\frac{1}{3}[/latex] или  [latex]5\frac{1}{6}-3\frac{1}{4}=(5-3)+(\frac{1}{6}-\frac{1}{4})=2+\frac{2-3}{12}=2-\frac{1}{12}=\frac{24-1}{12}=\frac{23}{12}=1\frac{11}{12}[/latex]