Контрольные задания
Вопрос:

1 вариант: 1) 1/2 + 2/3; 2) 3 − 4/5; 3) 3 1/3 + 5 3/4; 4) 6 1/2 − 2 2/3; 5) 1/2 × 2/3; 6) 2 2/15 × 1 9/16; 7) 4/15 : 12/35; 8) 9 : 1 4/5.

Фото задания: 1 вариант: 1) 1/2 + 2/3; 2) 3 − 4/5; 3) 3 1/3 + 5 3/4; 4) 6 1/2 − 2 2/3; 5) 1/2 × 2/3; 6) 2 2/15 × 1 9/16; 7) 4/15 : 12/35;…Фото задания

Ответ:

  1. \(\frac{1}{2}+\frac{2}{3}=\frac{3}{6}+\frac{4}{6}=\frac{7}{6}=1\frac{1}{6}\).
  2. \(3-\frac{4}{5}=\frac{15}{5}-\frac{4}{5}=\frac{11}{5}=2\frac{1}{5}\).
  3. \(3\frac{1}{3}+5\frac{3}{4}=8+\frac{4}{12}+\frac{9}{12}=8\frac{13}{12}=9\frac{1}{12}\).
  4. \(6\frac{1}{2}-2\frac{2}{3}=\frac{13}{2}-\frac{8}{3}=\frac{39-16}{6}=\frac{23}{6}=3\frac{5}{6}\).
  5. \(\frac{1}{2}\times\frac{2}{3}=\frac{2}{6}=\frac{1}{3}\).
  6. \(2\frac{2}{15}\times1\frac{9}{16}=\frac{32}{15}\times\frac{25}{16}=\frac{10}{3}=3\frac{1}{3}\).
  7. \(\frac{4}{15}:\frac{12}{35}=\frac{4}{15}\times\frac{35}{12}=\frac{7}{9}\).
  8. \(9:1\frac{4}{5}=9:\frac{9}{5}=9\times\frac{5}{9}=5\).

Ответ: 1) 1 1/6; 2) 2 1/5; 3) 9 1/12; 4) 3 5/6; 5) 1/3; 6) 3 1/3; 7) 7/9; 8) 5.