a: \(=\dfrac{2}{5}+\dfrac{3}{5}\cdot\dfrac{8}{3}=\dfrac{2}{5}+\dfrac{24}{15}=\dfrac{6+24}{15}=\dfrac{30}{15}=2\)
b: \(=5+\dfrac{3}{4}+1+\dfrac{2}{5}-3-\dfrac{3}{4}=3+\dfrac{2}{5}=\dfrac{17}{5}\)
c: \(=\dfrac{-20}{63}-\dfrac{12}{63}+\dfrac{1}{2}=\dfrac{-32}{63}+\dfrac{1}{2}=\dfrac{-64+63}{126}=-\dfrac{1}{126}\)
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