Вопрос:

Задание 124. Найдите произведения: 1–45.

Ответ:

Правило: чтобы умножить дроби, умножаем числители и знаменатели. Перед умножением сокращаем дроби. Натуральное число представляем дробью со знаменателем 1.

  1. \(\frac{2}{3}\cdot\frac{5}{8}=\frac{5}{12}\)
  2. \(\frac{1}{2}\cdot\frac{6}{7}=\frac{3}{7}\)
  3. \(\frac{3}{5}\cdot\frac{5}{8}=\frac{3}{8}\)
  4. \(\frac{1}{9}\cdot\frac{9}{10}=\frac{1}{10}\)
  5. \(\frac{6}{11}\cdot\frac{5}{18}=\frac{5}{33}\)
  6. \(\frac{2}{5}\cdot\frac{1}{3}=\frac{2}{15}\)
  7. \(\frac{1}{6}\cdot\frac{2}{7}=\frac{1}{21}\)
  8. \(\frac{2}{3}\cdot\frac{3}{13}=\frac{2}{13}\)
  9. \(\frac{1}{8}\cdot\frac{10}{11}=\frac{5}{44}\)
  10. \(\frac{3}{5}\cdot\frac{15}{19}=\frac{9}{19}\)
  11. \(\frac{2}{9}\cdot\frac{5}{9}=\frac{10}{81}\)
  12. \(\frac{5}{11}\cdot\frac{5}{6}=\frac{25}{66}\)
  13. \(\frac{4}{7}\cdot\frac{8}{9}=\frac{32}{63}\)
  14. \(\frac{3}{20}\cdot\frac{10}{11}=\frac{3}{22}\)
  15. \(\frac{3}{10}\cdot\frac{5}{9}=\frac{1}{6}\)
  16. \(\frac{5}{8}\cdot\frac{2}{15}=\frac{1}{12}\)
  17. \(\frac{2}{7}\cdot\frac{21}{22}=\frac{3}{11}\)
  18. \(\frac{8}{15}\cdot\frac{25}{32}=\frac{5}{12}\)
  19. \(\frac{12}{35}\cdot\frac{14}{15}=\frac{8}{25}\)
  20. \(\frac{2}{9}\cdot\frac{3}{8}=\frac{1}{12}\)
  21. \(\frac{7}{8}\cdot\frac{8}{40}=\frac{7}{40}\)
  22. \(\frac{27}{32}\cdot\frac{4}{5}=\frac{27}{40}\)
  23. \(\frac{45}{49}\cdot\frac{7}{10}=\frac{9}{14}\)
  24. \(\frac{12}{15}\cdot\frac{35}{36}=\frac{7}{9}\)
  25. \(\frac{18}{77}\cdot\frac{14}{27}=\frac{4}{33}\)
  26. \(\frac{22}{25}\cdot\frac{5}{33}=\frac{2}{15}\)
  27. \(\frac{48}{49}\cdot\frac{35}{16}=\frac{15}{7}\)
  28. \(\frac{7}{60}\cdot\frac{10}{21}=\frac{1}{18}\)
  29. \(\frac{12}{100}\cdot\frac{25}{4}=\frac{3}{4}\)
  30. \(4\cdot\frac{1}{6}=\frac{2}{3}\)
  31. \(7\cdot\frac{2}{7}=2\)
  32. \(9\cdot\frac{5}{18}=\frac{5}{2}=2\frac{1}{2}\)
  33. \(8\cdot\frac{3}{16}=\frac{3}{2}=1\frac{1}{2}\)
  34. \(12\cdot\frac{7}{18}=\frac{14}{3}=4\frac{2}{3}\)
  35. \(4\cdot\frac{3}{14}=\frac{6}{7}\)
  36. \(21\cdot\frac{5}{9}=\frac{35}{3}=11\frac{2}{3}\)
  37. \(44\cdot\frac{4}{33}=\frac{16}{3}=5\frac{1}{3}\)
  38. \(15\cdot\frac{3}{10}=\frac{9}{2}=4\frac{1}{2}\)
  39. \(43\cdot\frac{10}{43}=10\)
  40. \(22\cdot\frac{3}{26}=\frac{33}{13}=2\frac{7}{13}\)
  41. \(39\cdot\frac{4}{13}=12\)
  42. \(42\cdot\frac{6}{7}=36\)
  43. \(16\cdot\frac{1}{16}=1\)
  44. \(36\cdot\frac{4}{9}=16\)

Ответ: 1) \(\frac{5}{12}\); 2) \(\frac{3}{7}\); 3) \(\frac{3}{8}\); 4) \(\frac{1}{10}\); 5) \(\frac{5}{33}\); 6) \(\frac{2}{15}\); 7) \(\frac{1}{21}\); 8) \(\frac{2}{13}\); 9) \(\frac{5}{44}\); 10) \(\frac{9}{19}\); 11) \(\frac{10}{81}\); 12) \(\frac{25}{66}\); 13) \(\frac{32}{63}\); 14) \(\frac{3}{22}\); 15) \(\frac{1}{6}\); 16) \(\frac{1}{12}\); 17) \(\frac{3}{11}\); 18) \(\frac{5}{12}\); 19) \(\frac{8}{25}\); 20) \(\frac{1}{12}\); 21) \(\frac{7}{40}\); 22) \(\frac{27}{40}\); 23) \(\frac{9}{14}\); 24) \(\frac{7}{9}\); 25) \(\frac{4}{33}\); 26) \(\frac{2}{15}\); 27) \(\frac{15}{7}\); 28) \(\frac{1}{18}\); 29) \(\frac{3}{4}\); 30) \(\frac{2}{3}\); 31) \(2\); 32) \(\frac{5}{2}\); 33) \(\frac{3}{2}\); 34) \(\frac{14}{3}\); 35) \(\frac{6}{7}\); 36) \(\frac{35}{3}\); 37) \(\frac{16}{3}\); 38) \(\frac{9}{2}\); 39) \(10\); 40) \(\frac{33}{13}\); 41) \(12\); 42) \(36\); 43) \(1\); 44) \(16\).