a: \(=\dfrac{38}{45}-\dfrac{8}{45}+\dfrac{1}{3}+\dfrac{3}{11}=\dfrac{3}{11}+1=\dfrac{14}{11}\)
b: =-5/7(3/11+8/11)
=-5/7
c: \(=\dfrac{20}{5}\cdot\left(\dfrac{5}{1\cdot6}+\dfrac{5}{6\cdot11}+...+\dfrac{5}{101\cdot106}\right)\)
\(=4\left(1-\dfrac{1}{6}+\dfrac{1}{6}-\dfrac{1}{11}+...+\dfrac{1}{101}-\dfrac{1}{106}\right)\)
\(=4\cdot\dfrac{105}{106}=\dfrac{2}{53}\cdot105=\dfrac{210}{53}\)
d: \(=\dfrac{-2\cdot4-3\cdot2-3\cdot7}{35}=\dfrac{-2\cdot6-3\cdot7}{35}=\dfrac{-33}{35}\)
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