\[= \frac{- 55 + 58}{90}\ :\frac{38 - 35}{54} =\]
\[= \frac{3}{90}\ :\frac{3}{54} = \frac{1}{30}\ :\frac{1}{18} = \frac{18}{30} =\]
\[= \frac{6}{10} = \frac{3}{5} = 0,6\]