The Exponential Distribution · Exercise 40
According to the American Red Cross, about one out of nine people in the U.S. have Type B positive blood. Suppose the blood types of people arriving at a blood drive are independent. In this case, the number of Type B positive blood types that arrive roughly follows the Poisson distribution.
(a) If 100 people arrive, how many on average would be expected to have Type B positive blood?
(b) What is the probability that over 10 people out of these 100 have type B positive blood?
(c) What is the probability that more than 20 people arrive before a person with type B positive blood is found?
OpenStax, Introductory Statistics 2e · §5.3 The Exponential Distribution · Exercise 40
No hints for this one.
Check your full solution
Upload photos of your handwritten work or a PDF, and Lemma will read it and tell you whether it's right — and where it first goes wrong if not.