Вопрос:

Задание 110. Найдите значение выражения: 1) \(3\frac{6}{7}-1\frac{2}{7}+2\frac{3}{7}\); 2) \(1\frac{4}{19}+5\frac{11}{19}-4\frac{12}{19}\); 3) \(4\frac{8}{11}-2\frac{5}{11}-1\frac{1}{11}\); 4) \(2\frac{6}{7}+5\frac{5}{7}-4\frac{4}{7}\); 5) \(8\frac{1}{9}+3\frac{8}{9}-9\frac{4}{9}\); 6) \(1\frac{14}{17}+1\frac{12}{17}-1\frac{10}{17}\); 7) \(7\frac{11}{21}+5\frac{8}{21}+2\frac{10}{21}\); 8) \(15\frac{3}{7}-7\frac{4}{7}-2\frac{6}{7}\); 9) \(12\frac{3}{11}-5\frac{6}{11}+1\frac{9}{11}\); 10) \(8\frac{2}{31}-7\frac{17}{31}+2\frac{30}{31}\).

Ответ:

  1. \[3\frac{6}{7}-1\frac{2}{7}+2\frac{3}{7}=(3-1+2)+\frac{6-2+3}{7}=4+1=5.\] Ответ: \(5\).
  2. \[1\frac{4}{19}+5\frac{11}{19}-4\frac{12}{19}=(1+5-4)+\frac{4+11-12}{19}=2\frac{3}{19}.\] Ответ: \(2\frac{3}{19}\).
  3. \[4\frac{8}{11}-2\frac{5}{11}-1\frac{1}{11}=(4-2-1)+\frac{8-5-1}{11}=1\frac{2}{11}.\] Ответ: \(1\frac{2}{11}\).
  4. \[2\frac{6}{7}+5\frac{5}{7}-4\frac{4}{7}=(2+5-4)+\frac{6+5-4}{7}=3+1=4.\] Ответ: \(4\).
  5. \[8\frac{1}{9}+3\frac{8}{9}-9\frac{4}{9}=(8+3-9)+\frac{1+8-4}{9}=2\frac{5}{9}.\] Ответ: \(2\frac{5}{9}\).
  6. \[1\frac{14}{17}+1\frac{12}{17}-1\frac{10}{17}=(1+1-1)+\frac{14+12-10}{17}=1\frac{16}{17}.\] Ответ: \(1\frac{16}{17}\).
  7. \[7\frac{11}{21}+5\frac{8}{21}+2\frac{10}{21}=(7+5+2)+\frac{11+8+10}{21}=14+\frac{29}{21}=15\frac{8}{21}.\] Ответ: \(15\frac{8}{21}\).
  8. \[15\frac{3}{7}-7\frac{4}{7}-2\frac{6}{7}=(15-7-2)+\frac{3-4-6}{7}=6-1\frac{1}{7}=4\frac{6}{7}.\] Ответ: \(4\frac{6}{7}\).
  9. \[12\frac{3}{11}-5\frac{6}{11}+1\frac{9}{11}=(12-5+1)+\frac{3-6+9}{11}=8+\frac{6}{11}=8\frac{6}{11}.\] Ответ: \(8\frac{6}{11}\).
  10. \[8\frac{2}{31}-7\frac{17}{31}+2\frac{30}{31}=(8-7+2)+\frac{2-17+30}{31}=3+\frac{15}{31}=3\frac{15}{31}.\] Ответ: \(3\frac{15}{31}\).