SRMJEE 2016 Paper with key

Let u1 and u2 be two wins such that u1 contains 3 white and 2 red balls and u2 contains only one white ball. A fair coin is tossed. If head appear then one ball is drawn at random from u1 and put into u2. However if tail appears then 2 balls are drawn at random from u1 and put into u2. Now one ball is drawn at random from u2. Then the probability of the drawn ball from u2 being white is