Airlines sometimes overbook ights. Suppose that for a plane with 50 seats, 55 passengers have tickets. Dene the random variable Y as the number of ticketed passengers who actually show up for the ight. The probability mass function of Y appears in the accompanying table. y 45 46 47 48 49 50 51 52 53 54 55 p(y) 0.05 0.10 0.12 0.14 0.25 0.17 0.06 0.05 0.03 0.02 0.01