Решение:
- \( 2\frac{1}{3} - 3,5 = \frac{7}{3} - \frac{35}{10} = \frac{7}{3} - \frac{7}{2} = \frac{14}{6} - \frac{21}{6} = -\frac{7}{6} \)
- \( -\frac{7}{6} : (-\frac{5}{6}) = -\frac{7}{6} \cdot (-\frac{6}{5}) = \frac{7}{5} \)
- \( \frac{7}{5} + 0,42 = \frac{7}{5} + \frac{42}{100} = \frac{7}{5} + \frac{21}{50} \)
- \( \frac{70}{50} + \frac{21}{50} = \frac{91}{50} \)
Ответ: \(\frac{91}{50}\).