It is estimated that 55% of the freshmen entering a particular college will graduate from that college in four years.
a. For a random sample of 5 entering freshmen, what is the probability that exactly 3 will graduate in four years?
b. For a random sample of 5 entering freshmen, what is the probability that a majority will graduate in four years?
c. 80 entering freshmen are chosen at random. Find the mean and standard deviation of the proportion of these 80 that will graduate in four years.