Ответ:

  1. Приведём дробные части к общему знаменателю: \(7\frac{1}{5}-8\frac{1}{8}+9\frac{3}{4}=\frac{36}{5}-\frac{65}{8}+\frac{39}{4}=\frac{288-325+312}{40}=\frac{275}{40}=6\frac{7}{8}\).

  2. \(7\frac{11}{16}-6\frac{7}{8}+3\frac{3}{4}=\frac{123}{16}-\frac{110}{16}+\frac{60}{16}=\frac{73}{16}=4\frac{9}{16}\).

  3. \(8\frac{21}{40}-5\frac{5}{8}+9\frac{3}{5}=\frac{341}{40}-\frac{225}{40}+\frac{384}{40}=\frac{500}{40}=12\frac{1}{2}\).

  4. \(11\frac{3}{25}-2\frac{1}{4}-7\frac{7}{50}=\frac{556}{50}-\frac{125}{50}-\frac{357}{50}=\frac{74}{50}=1\frac{12}{25}\).

  5. \(2\frac{13}{20}+4\frac{7}{40}-23\frac{8}{500}=\frac{1060}{400}+\frac{1670}{400}-\frac{9208}{400}=-\frac{6478}{400}=-16\frac{39}{200}\).

  6. \(9\frac{9}{10}+3\frac{2}{3}-15\frac{123}{200}=\frac{5940+2200-9369}{600}=-\frac{1229}{600}=-2\frac{29}{600}\).