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