\(a,=\dfrac{5}{17}+\dfrac{-3}{17}=\dfrac{2}{17}\\ b,=\dfrac{5}{12}+\dfrac{6}{12}=\dfrac{11}{12}\\ c,=\left(\dfrac{-6}{15}+\dfrac{5}{15}\right)\cdot\left(\dfrac{21}{14}-\dfrac{6}{14}\right)\\ =\dfrac{-1}{15}\cdot\dfrac{15}{14}=\dfrac{-1}{14}\\ d,=\left(\dfrac{4}{7}-\dfrac{3}{28}\right)+\dfrac{-5}{8}\\ =\left(\dfrac{16}{28}-\dfrac{3}{28}\right)+\dfrac{-5}{8}\\ =\dfrac{13}{28}+\dfrac{-5}{8}\\ =\dfrac{-9}{56}\\ e,=\dfrac{1}{5}:\dfrac{1}{10}-\dfrac{1}{3}\cdot\dfrac{-17}{12}\\ =2-\dfrac{-4}{17}=\dfrac{38}{17}\)
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