Задание

Вычислите наиболее удобным способом:

\(\frac{2}{7}\cdot\frac{14}{15}+\frac{2}{49}\cdot\frac{14}{15}-\frac{1}{7}\cdot\frac{14}{15}+\frac{3}{49}\cdot\frac{14}{15}\)

\(\frac{17}{18}\cdot(\frac{7}{35}\cdot\frac{18}{34})\)

\(\frac{1}{7}\cdot9\cdot21\cdot\frac{1}{9}\)

\(\frac{3}{10}\cdot\frac{5}{6}+\frac{5}{6}\cdot\frac{9}{10}\)

\(\frac{3}{10}\cdot(\frac{3}{4}-\frac{5}{12})\cdot2\)

\(\frac{1}{10}\)

\(\frac8{35}\)

1

\(\frac1{5}\)

3