A specific automotive part that a service station stocks in its inventory has an 8% chance of being defective. Suppose many cars come into the service station needing this
Part each week. What is the expected number of parts retrieved until the first defective?
A) 8
B) 12.5
C) 10.5
D) 15
E) 20

Question

Quizplus · Accepted Answer

The expected number of trials until the first success in a geometric distribution is given by 1/p, where p is the probability of success (in this case, finding a defective part). Given an 8% chance (or 0.08 probability) of being defective, the expected number is 1/0.08 = 12.5.

A Specific Automotive Part That a Service Station Stocks in Its