The Piggy Banks Problem - 003
Two piggy banks contains some coins. The first piggy bank contains 4 fair coins and 2 biased coins in favor of heads. The second piggy bank contains 2 fair coins and 4 biased coins in favor of tails. The biased coins follow the odds 2:1. A piggy bank is selected and a coin is obtained from it. The coin is tossed and a head appears. What is the probability that the coin is biased if each piggy bank has an equal chance of being selected?