In: Statistics and Probability
Suppose that only 0.1% of all computers of a certain type experience CPU failure during the warranty period. Consider a sample of 10, 000 computers. Let the random variable X equals the number of computers in the sample that have the defect. (a) What is the distribution of X? Write down its p.m.f.
(b) Give expression for the probability that exactly 56 computers will have the defect.
(c) What are the expected value and standard deviation of X?
(d) Approximate X by another distribution and give the p.m.f. of the approximated distribution.
(e) What is the approximate probability that more than 10 computers will have the defect?
(f) What is the approximate probability that between 10 and 20 (both inclusive) computers will have the defect?