7. (13 points) CSUN Statistics department purchased 24 Dell laptops from a dealer in order to have a supply on
hand for tests for use by students who forget to bring their own. Although the department was not aware of this,
five of the laptops were defective. When a test is being written, students who have forgotten their own laptops
are allowed to select at random one of the Department's. Suppose at the first test of the term, four students
forgot to bring their laptops. Let X is the number of defective laptops.
a. Name the distribution of r.v. X.
b. What is a set of values of r.v. X?
c. What is the probability that at least two of these students select a defective laptop?
d. What is the probability that at most one of these students select a defective laptop?
e. What is the probability distribution function of defective laptops?