If the number of red balls , Green balls and Blue balls from bag A are 3, 5, and 7 respectively and the number of red balls , Green balls and Blue balls from bag B are 8, 7 and 5 respectively. 25% of the red balls from bag B are taken out and placed into bag A and 'y' number of blue balls are taken out from bag A and placed into bag B. If the probability of picking a blue ball from bag B is 2/21 more than the probability of picking a blue ball from bag A, then find the value of y.