The question is:
There are two boxes denoted as Box-1 & Box-2. In Box-1 there are 5 red and 4 white balls and in Box-2 there are 3 red and 4 white balls. Then, two balls of same colored have been placed placed into Box-2 from Box-1. Later, a ball was taken from Box-2 and it was seen that the ball is red. What is the probability that the red ball was in Box-1 initially?
I tried to solve it using bayes theorem. But I couldn't settle it correctly. Need some help. Thanks