\[2\frac{5}{6} \cdot 6\frac{2}{3} + \frac{3}{10} \cdot 6\frac{2}{3} - 6\frac{2}{3} \cdot 1\frac{1}{3} =\]
\[= 6\frac{2}{3} \cdot \left( 2\frac{5^{\backslash 5}}{6} + \frac{3^{\backslash 3}}{10} - 1\frac{1^{\backslash 10}}{3} \right) =\]
\[= \frac{20}{3} \cdot 1\frac{25 + 9 - 10}{30} =\]
\[= \frac{20}{3} \cdot 1\frac{24}{30} = \frac{20}{3} \cdot 1\frac{4}{5} = \frac{20 \cdot 9}{3 \cdot 5} =\]
\[= 4 \cdot 3 = 12\]