\(\dfrac{8}{18}+\dfrac{11}{18}-\dfrac{15}{18}=\dfrac{8+11-15}{18}=\dfrac{4}{18}=\dfrac{2}{9}\)
\(\dfrac{4}{9}+\dfrac{11}{18}-\dfrac{5}{6}=\dfrac{8}{18}+\dfrac{11}{18}-\dfrac{15}{18}=\dfrac{4}{18}=\dfrac{2}{9}\)
\(=\dfrac8{18} - \dfrac56= \dfrac8{18} - \dfrac{24}{18} = \dfrac{-16}{18}\)