\[m - \frac{2}{11}m = 9,9\]
\[m\left( 1 - \frac{2}{11} \right) = 9,9\]
\[m\left( \frac{11 - 2}{11} \right) = 9,9\]
\[\frac{9}{11}m = 9,9\]
\[m = 9,9\ :\frac{9}{11}\]
\[m = \frac{99}{10} \cdot \frac{11}{9} =\]
\[m = \frac{9 \cdot 11 \cdot 11}{10 \cdot 9} = \frac{121}{10}\]
\[m = 12,1.\]
\[Ответ:\ \ m = 12,1.\]