Ответ:

1) \(-3,4+7=3,6=\frac{18}{5}\).

\(-1\frac{7}{18}=-\frac{25}{18}\).

\(\frac{18}{5}\cdot\left(-\frac{25}{18}\right)=-5\).

2) \(6\frac{2}{9}=\frac{56}{9}\), \(5\frac{5}{6}=\frac{35}{6}\).

\(\frac{56}{9}-\frac{35}{6}=\frac{112}{18}-\frac{105}{18}=\frac{7}{18}\).

\(\frac{7}{18}:\left(-\frac{7}{36}\right)=\frac{7}{18}\cdot\left(-\frac{36}{7}\right)=-2\).

Ответ: 1) −5; 2) −2.