Ответ:

  1. \(10\frac{11}{23}-2\frac{8}{23}=8\frac{3}{23}\).
  2. \(9\frac{2}{27}-3\frac{25}{27}=8\frac{29}{27}-3\frac{25}{27}=5\frac{4}{27}\).
  3. \(7\frac{21}{29}-6\frac{28}{29}=6\frac{50}{29}-6\frac{28}{29}=\frac{22}{29}\).
  4. \(16\frac{11}{15}-11\frac{11}{15}=5\).

Ответ: а) \(8\frac{3}{23}\); б) \(5\frac{4}{27}\); в) \(\frac{22}{29}\); г) \(5\).