Контрольные задания
Вопрос:Фото задания: 3. Вычислите: 1) \(1\frac{7}{18}-\frac{4}{15}\); 2) \(4\frac{1}{5}-4\frac{1}{6}\); 3) \(3\frac{1}{9}\cdot4\frac{2}{5}\); 4)…Фото задания

Ответ:

  1. \(1\frac{7}{18}-\frac{4}{15}=\frac{25}{18}-\frac{4}{15}=\frac{125-24}{90}=\frac{101}{90}=1\frac{11}{90}\).
  2. \(4\frac{1}{5}-4\frac{1}{6}=\frac{21}{5}-\frac{25}{6}=\frac{126-125}{30}=\frac{1}{30}\).
  3. \(3\frac{1}{9}\cdot4\frac{2}{5}=\frac{28}{9}\cdot\frac{22}{5}=\frac{616}{45}=13\frac{31}{45}\).
  4. \((30:27-\frac{1}{3})\cdot2\frac{1}{7}+\frac{2}{5}=(\frac{10}{9}-\frac{1}{3})\cdot\frac{15}{7}+\frac{2}{5}=\frac{7}{9}\cdot\frac{15}{7}+\frac{2}{5}=\frac{5}{3}+\frac{2}{5}=\frac{31}{15}=2\frac{1}{15}\).

Ответ: 1) \(1\frac{11}{90}\); 2) \(\frac{1}{30}\); 3) \(13\frac{31}{45}\); 4) \(2\frac{1}{15}\).