Вопрос:

3. Вычислите: \((30:27-\frac{1}{3})\cdot2-\frac{1}{7}+\frac{2}{5}\).

Ответ:

\(30:27=\frac{10}{9}\).

\(\frac{10}{9}-\frac{1}{3}=\frac{10}{9}-\frac{3}{9}=\frac{7}{9}\).

\(\frac{7}{9}\cdot2=\frac{14}{9}\).

\(-\frac{1}{7}+\frac{2}{5}=\frac{-5+14}{35}=\frac{9}{35}\).

\(\frac{14}{9}+\frac{9}{35}=\frac{490+81}{315}=\frac{571}{315}=1\frac{256}{315}\).

Ответ: \(1\frac{256}{315}\).