Quick question (hopefully) on conditional probability. The question says, Consider a Biased coin, where the chance of heads is 2/3 and tails is 1/3. If the coin shows tails, a chip is drawn from urn 1, and if heads, drawn from urn 2. Urn 1 has 3 white chips and four red chips. Urn 2 has 6 white and 3 red chips. Chips drawn from the urns are not replaced. What is the probability that a white chip will be drawn on the second toss?
We have stared at this question for ages and so far have only figured that we could be able to use a tree diagram to figure this out, any help would be appreciated. Thanks!!