\(=\dfrac{2}{7}+\dfrac{12}{7}+4\times\dfrac{2}{7}-\dfrac{2}{7}\\ =\dfrac{2}{7}\times\left(1+4-1\right)+\dfrac{12}{7}\\ =\dfrac{2}{7}\times4+\dfrac{12}{7}\\ =\dfrac{8}{7}+\dfrac{12}{7}=\dfrac{12+8}{7}=\dfrac{20}{7}\)
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