If x = 3t, y = $$\frac{1}{2}$$(t + 1), then the value of t for which x = 2y is?

$$\eqalign{ & x = 3t\,......(i) \cr & y = \frac{1}{2}\left( {t + 1} \right) \cr & x = 2y \cr & \Rightarrow x = 2 \times \frac{1}{2}\left( {t + 1} \right) \cr & \Rightarrow x = t + 1\,......(ii) \cr & \therefore 3t = t + 1 \cr & \left( {{\text{From equation (i) and (ii)}}} \right) \cr & \Rightarrow 2t = 1 \cr & \Rightarrow t = \frac{1}{2} \cr} $$