Find the reciprocal of the following:
(i) \((\dfrac{1}{2} \times \dfrac{1}{4}) + (\dfrac{1}{2} \times 6)\)
(ii) \(\dfrac{20}{51} \times \dfrac{4}{91}\)
(iii) \(\dfrac{3}{13} \div \dfrac{-4}{65}\)
(iv) \((-5 \times \dfrac{12}{15}) - (-3 \times \dfrac{2}{9})\)
(i) \(\dfrac{8}{25}\)
(ii) \(\dfrac{4641}{80}\)
(iii) \(-\dfrac{4}{15}\)
(iv) \(-\dfrac{3}{10}\)
Each expression is simplified first, then reciprocal is taken.