(Solved): fast! 3) Box A contains 2 red chips and 3 white chips; box B contains 1 red chip and 2 white chips; ...

3) Box $\mathbf{A}$ contains 2 red chips and $3$ white chips; box $\mathbf{B}$ contains 1 red chip and $2$ white chips; and box $\mathbf{C}$ contains 4 red chips and 2 white chips. a) If a box is selected at random, and one chip is taken at random from that box. What is the probability of selecting a white chip? b) If the selected chip is white, what is the probability that it was selected from box C?