Q: "A ball is chosen at random from an urn containing 2 red and 3 green balls and is then added to a second urn which initially contains 2 green and 3 white balls. The balls in the second urn are then mixed and one is chosen at random. If this ball is green, what is the probability that the ball taken from the first urn was also green?"
At first glance this seems like a conditional probability question, am I on the right track or is this completely wrong? Can someone tell me how to approach this?