SOLUTION: 2. Approximately 20% of the population belongs to a health maintenance organization (HMO). Assume that for a randomly selected group of 20 adults, the number belonging to an HMO ha

Algebra ->  Probability-and-statistics -> SOLUTION: 2. Approximately 20% of the population belongs to a health maintenance organization (HMO). Assume that for a randomly selected group of 20 adults, the number belonging to an HMO ha      Log On


   

Question 574069: 2. Approximately 20% of the population belongs to a health maintenance organization (HMO). Assume that for a randomly selected group of 20 adults, the number belonging to an HMO has a binomial distribution.
a. What is the probability of finding exactly 5 in the 20 who belong to an HMO?
b. What is the probability of finding at least one in the 20 who belongs to an HMO?
Answer by reviewermath(1029) About Me  (Show Source):
You can put this solution on YOUR website!
Let X = the number belonging to an HMO
a. P(X = 5) = %28matrix%28+2%2C+1%2C+20%2C+5%29%29%2A%280.2%5E5%29%2A%280.8%5E15%29
= 0.17456
b. P%28X%3E=1%29+=+1+-+P%28X=0%29
= 1+-+%28matrix%28+2%2C+1%2C+20%2C+0%29%29%2A%280.2%5E0%29%2A%280.8%5E20%29
= 0.98847