1. AP Statistics Section 8.2: The Geometric Distribution

2. Objective: To be able to understand and calculate geometric probabilities. Ex. Russian Roulette Criteria for a Geoemtric Random Variable: 1.Each observation can be classified as a success or failure. 2.p is the probability of success and p is fixed. 3.The observations are independent. 4.The random variable measures the number of trials necessary to obtain the first success. (it includes the 1 st success)

3. 123…n… …… ……

5. Ex. Suppose you work at a blood bank and are interested in collecting type A blood. It is known that 15% of the population is type A. Let X represent the number of donors until and including the first type A donor is found. a.Does this example meet the criteria for a geometric setting? b.Find probability that the first type A donor is the 4 th donor of the day. c.Find probability that the first type A donor is the 2 nd donor of the day. d.Find probability that the first type A donor occurs before the 4 th donor of the day.

6. e.Find probability that the first type A donor is at least the 5 th donor of the day. f.Complete the probability distribution for the geometric random variable X for the first 6 terms.