13. \(\left(2\frac{4}{7}-1,2\right)\cdot5\frac{5}{6}\)

Преобразуем числа: \(2\frac{4}{7}=\frac{18}{7}\), \(1,2=\frac{6}{5}\), \(5\frac{5}{6}=\frac{35}{6}\).

\(\frac{18}{7}-\frac{6}{5}=\frac{90-42}{35}=\frac{48}{35}\).

\(\frac{48}{35}\cdot\frac{35}{6}=\frac{48}{6}=8\).

Ответ: \(8\).