\[\left( 3\frac{1}{8} - 2\frac{5}{12} \right) \cdot \left( - 1\frac{3}{17} \right) =\]
\[= \left( 3\frac{1 \cdot 3}{24} - 2\frac{5 \cdot 2}{24} \right) \cdot \left( - \frac{20}{17} \right) =\]
\[= \left( 3\frac{3}{24} - 2\frac{10}{24} \right) \cdot \left( - \frac{20}{17} \right) =\]
\[= \left( 2\frac{27}{24} - 2\frac{10}{24} \right) \cdot \left( - \frac{20}{17} \right) = \frac{17}{24} \cdot \left( - \frac{20}{17} \right) =\]
\[= - \frac{17 \cdot 20}{24 \cdot 17} = - \frac{1 \cdot 5}{6 \cdot 1} = - \frac{5}{6}\text{.\ }\]