Trains X and Y arrive at a station at random between 8 A.M. and 8.20 A.M. Train
X stops for four minutes and train Y stops for five minutes. Assuming that the trains
arrive independently of each other.

(a) Determine the probability that train X arrives before train Y.

(b) Determine the probability that the trains meet at the station.
(c) Assuming that the trains met, determine the probability that train X arrived before train Y.