{2\frac{1}{3}-[(4\frac{1}{2}-1\frac{2}{3}):(4+1\frac{2}{3})]}:(1-\frac{1}{4})=
2\frac{1}{3}-[(\frac{9}{2}-\frac{5}{3}):5\frac{2}{3}]:\frac{3}{4}=
2\frac{1}{3}-(\frac{27-10}{6}:\frac{17}{3}]:\frac{3}{4}=
2\frac{1}{3}-\frac{17}{6}*\frac{3}{17}*\frac{4}{3}=
\frac{7}{3}-\frac{2}{3}=\frac{5}{3}