Вопрос:

50. Выполните умножение: 1) 3/7 · 5/6 · 7/5; 2) 7/11 · 3/31 · 11/7; 3) 13/8 · 10/13 · 3/10; 4) 15/77 · (11/9 · 1 1/20); 5) 2/3 · 5/4 · 9/5; 6) 4/25 · 10/18 · 15/16; 7) 30/55 · 5/18 · 3/25; 8) 12/13 · 13/7 · 7/16; 9) 4/7 · 35/36 · 3/25; 10) 20/13 · 39/200 · 10/21; 11) 40/33 · 11/18 · 3/5; 12) (1 3/4 · 13/16) · 16/39.

Ответ:

  1. \(\frac{3}{7}\cdot\frac{5}{6}\cdot\frac{7}{5}=\frac{1}{2}\).
  2. \(\frac{7}{11}\cdot\frac{3}{31}\cdot\frac{11}{7}=\frac{3}{31}\).
  3. \(\frac{13}{8}\cdot\frac{10}{13}\cdot\frac{3}{10}=\frac{3}{8}\).
  4. \(\frac{15}{77}\cdot\left(\frac{11}{9}\cdot1\frac{1}{20}\right)=\frac{15}{77}\cdot\frac{11}{9}\cdot\frac{21}{20}=\frac{3}{20}\).
  5. \(\frac{2}{3}\cdot\frac{5}{4}\cdot\frac{9}{5}=\frac{3}{2}=1\frac{1}{2}\).
  6. \(\frac{4}{25}\cdot\frac{10}{18}\cdot\frac{15}{16}=\frac{1}{12}\).
  7. \(\frac{30}{55}\cdot\frac{5}{18}\cdot\frac{3}{25}=\frac{1}{55}\).
  8. \(\frac{12}{13}\cdot\frac{13}{7}\cdot\frac{7}{16}=\frac{3}{4}\).
  9. \(\frac{4}{7}\cdot\frac{35}{36}\cdot\frac{3}{25}=\frac{1}{15}\).
  10. \(\frac{20}{13}\cdot\frac{39}{200}\cdot\frac{10}{21}=\frac{1}{14}\).
  11. \(\frac{40}{33}\cdot\frac{11}{18}\cdot\frac{3}{5}=\frac{4}{45}\).
  12. \(\left(1\frac{3}{4}\cdot\frac{13}{16}\right)\cdot\frac{16}{39}=\frac{7}{12}\).