\(\left(5+\dfrac{1}{5}-\dfrac{2}{9}\right)-\left(2-\dfrac{1}{23}-\dfrac{73}{35}+\dfrac{5}{6}\right)-\left(8+\dfrac{2}{7}-\dfrac{1}{18}\right)\)
\(=5+\dfrac{1}{5}-\dfrac{2}{9}-2+\dfrac{1}{23}+\dfrac{73}{35}-\dfrac{5}{6}-8-\dfrac{2}{7}+\dfrac{1}{18}\)
\(=\left(5-2-8\right)+\left(\dfrac{1}{5}+\dfrac{73}{35}-\dfrac{2}{7}\right)+\left(\dfrac{2}{9}-\dfrac{5}{6}+\dfrac{1}{18}\right)+\dfrac{1}{23}\)
\(=\left(-5\right)+\left(\dfrac{7}{35}+\dfrac{73}{35}-\dfrac{10}{35}\right)+\left(\dfrac{4}{18}-\dfrac{15}{18}+\dfrac{1}{18}\right)+\dfrac{1}{23}\)
\(=\left(-5\right)+2+\dfrac{-5}{9}+\dfrac{1}{23}\)
\(=\left(-3\right)+\dfrac{-5}{9}+\dfrac{1}{23}=\dfrac{-727}{207}\)
