\[\left( 5\frac{1}{4} - 6\frac{1}{6} \right) \cdot \left( 3\frac{1}{4} - 0,55 \right) =\]
\[= - \left( 6\frac{2}{12} - 5\frac{3}{12} \right) \cdot \left( 3\frac{1}{4} - \frac{55}{100} \right) =\]
\[= - \left( 5\frac{14}{12} - 5\frac{3}{12} \right) \cdot \left( 3\frac{1}{4} - \frac{11}{20} \right) =\]
\[= - \frac{11}{12} \cdot \left( 3\frac{5}{20} - \frac{11}{20} \right) =\]
\[= - \frac{11}{12} \cdot \left( 2\frac{25}{20} - \frac{11}{20} \right) =\]
\[= - \frac{11}{12} \cdot 2\frac{14}{20} = - \frac{11 \cdot 54}{12 \cdot 20} =\]
\[= - \frac{99}{40} = - 2\frac{19}{40}\]