luke takes bus 21a to the purdue campus every day. luke's arrival time at the bus stop is a random variable x which is uniformly distributed between 8:20 a.m. and 8:30 a.m. the departure time of the bus from that stop is a random variable y which is uniformly distributed between 8:25 a.m. and 8:35 a.m. suppose x and y are independent, what is the probability that luke can catch the bus?