Task 1

The number of students who login to a randomly selected computer in a college computer lab
follows a Poisson probability distribution with a mean of 19 students per day.

a. Using the Poisson probability distribution formula, determine the probability that exactly 12 stu-
dents will login to a randomly selected computer at this lab on a given day.

b. Using the Poisson probability distribution table, determine the probability that the number of stu-
dents who will login to a randomly selected computer at this lab on a given day is
i. from 13 to 16
ii. fewer than 8

Task 2

According to a Harris Interactive poll, 52% of American college graduates have Facebook accounts
(http://www.harrisinteractive.com/harris_poll/pubs/Harris_Poll_2009_04_16.pdf). Suppose that this result is true for the current population of American college graduates.

a. Let x be a binomial random variable that denotes the number of American college graduates in
a random sample of 15 who have Facebook accounts. What are the possible values that x can
assume?

b. Find the probability that exactly 9 American college graduates in a sample of 15 have Face-
book accounts.