1) (2/3 − 1/6) : 9/5 + 3/10 : 1/5 − 1

\((\frac{2}{3}-\frac{1}{6}):\frac{9}{5}+\frac{3}{10}:\frac{1}{5}-1\)

\(\frac{2}{3}-\frac{1}{6}=\frac{1}{2}\)

\(\frac{1}{2}:\frac{9}{5}=\frac{1}{2}\cdot\frac{5}{9}=\frac{5}{18}\)

\(\frac{3}{10}:\frac{1}{5}=\frac{3}{10}\cdot5=\frac{3}{2}\)

\(\frac{5}{18}+\frac{3}{2}-1=\frac{5}{18}+\frac{27}{18}-\frac{18}{18}=\frac{14}{18}=\frac{7}{9}\)

Ответ: \(\frac{7}{9}\)