Ответ:

\(\frac{5}{18}-\frac{11}{12}=\frac{10-33}{36}=-\frac{23}{36}\).

\(-\frac{23}{36}:\frac{5}{9}=-\frac{23}{36}\cdot\frac{9}{5}=-\frac{23}{20}=-1.15\).

Ответ: \(-1.15\).