a: =9+5/8+11+7/8
=20+3/2
=21,5
b: \(=\dfrac{53}{8}:\dfrac{15}{4}=\dfrac{53}{8}\cdot\dfrac{4}{15}=\dfrac{53}{30}\)
c: \(=\dfrac{15}{8}:\dfrac{-17}{4}=\dfrac{15}{8}\cdot\dfrac{-4}{17}=\dfrac{-15}{34}\)
g: \(=\dfrac{3}{4}\cdot\dfrac{5}{2}:\left(\dfrac{3}{4}\cdot5\right)=\dfrac{15}{8}:\dfrac{15}{4}=\dfrac{1}{2}\)