Mail rooms contaminated with anthrax. In Chance (Spring 2002), research statisticians discussed the problem of sampling mail rooms for the presence of anthrax spores.

Let x equal the number of mail rooms contaminated with anthrax spores in a random sample of 3 mail rooms selected from a population of 100 mail rooms. If 20 of the 100 mail rooms are contaminated with anthrax, researchers LO9 showed that the probability distribution for x is given by the formula p1x2 =

a20 x

b a 80 3 - x b

a100 3

b

a. What is the name given to this probability distribution?

b. Specify r, N, and n for this distribution.

c. Find p102.

d. Find p112.

e. Find p122.

f. Find p132.