4) (1 1/35 : 4/5 − 1 8/35) · 3 1/3

\(1\frac{1}{35}:\frac{4}{5}=\frac{36}{35}\cdot\frac{5}{4}=\frac{9}{7}=\frac{45}{35}\).

В скобках: \(\frac{45}{35}-1\frac{8}{35}=\frac{45}{35}-\frac{43}{35}=\frac{2}{35}\).

\(\frac{2}{35}\cdot3\frac{1}{3}=\frac{2}{35}\cdot\frac{10}{3}=\frac{4}{21}\).

Ответ: \(\frac{4}{21}\).