Вопрос:

Задание 2. Вычислите: а) \(3\frac{1}{4}-5\); б) \(-2\frac{3}{5}+4\frac{1}{3}\); в) \(5\frac{1}{2}-3\frac{3}{4}\); г) \(-3\frac{2}{3}\cdot6\); д) \(\frac{5}{8}:(-24)\); е) \(-18:\left(-\frac{2}{9}\right)\); ж) \(-4\frac{1}{2}\cdot\left(-2\frac{2}{3}\right)\).

Ответ:

  1. \(3\frac{1}{4}-5=\frac{13}{4}-\frac{20}{4}=-\frac{7}{4}=-1\frac{3}{4}\).
  2. \(-2\frac{3}{5}+4\frac{1}{3}=-\frac{13}{5}+\frac{13}{3}=\frac{-39+65}{15}=\frac{26}{15}=1\frac{11}{15}\).
  3. \(5\frac{1}{2}-3\frac{3}{4}=\frac{11}{2}-\frac{15}{4}=\frac{22}{4}-\frac{15}{4}=\frac{7}{4}=1\frac{3}{4}\).
  4. \(-3\frac{2}{3}\cdot6=-\frac{11}{3}\cdot6=-22\).
  5. \(\frac{5}{8}:(-24)=\frac{5}{8}\cdot\left(-\frac{1}{24}\right)=-\frac{5}{192}\).
  6. \(-18:\left(-\frac{2}{9}\right)=(-18)\cdot\left(-\frac{9}{2}\right)=81\).
  7. \(-4\frac{1}{2}\cdot\left(-2\frac{2}{3}\right)=-\frac{9}{2}\cdot\left(-\frac{8}{3}\right)=12\).

Ответ: а) \(-1\frac{3}{4}\); б) \(1\frac{11}{15}\); в) \(1\frac{3}{4}\); г) \(-22\); д) \(-\frac{5}{192}\); е) \(81\); ж) \(12\).