Question

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Answer 1

\(\dfrac{7}{2}-\left(\dfrac{3}{4}+\dfrac{1}{5}\right)\\ =\dfrac{7}{2}-\left(\dfrac{15}{20}+\dfrac{4}{20}\right)\\ =\dfrac{7}{2}-\dfrac{19}{20}\\ =\dfrac{70}{20}-\dfrac{19}{20}\\ =\dfrac{51}{20}\)