Ответ:

  1. \(−3\frac{1}{8}\cdot16=−\frac{25}{8}\cdot16=−50\).
  2. \(−2\frac{4}{5}: (−1.7)=−\frac{14}{5}:−\frac{17}{10}=\frac{28}{17}\).
  3. \(−2.84−5.49=−8.33\).
  4. \(−2−(−6)−8=−2+6−8=−4\).
  5. \(3\frac{3}{4}−5\frac{5}{6}=\frac{15}{4}−\frac{35}{6}=\frac{45−70}{12}=−\frac{25}{12}=−2\frac{1}{12}\).

Ответ: −50; \(\frac{28}{17}\); −8,33; −4; \(−2\frac{1}{12}\).