Question

At a medium sized airport, mechanics need to replace tires on some of the airplanes each week because the tread on the tires is below the safe limit. You collected 36 weeks of data and observed that the numbers followed a Poisson distribution and that there was an average of 2 tires replaced per week.
1) What is the lambda value for the Poisson distribution?

Select one:

a. 0

b. 1/2

c. 1

d. 2

e. sqrt(1/2)

2) The the time between incoming customer service calls to a computer-repair hotline follows an exponential distribution with an expectation of 2 minutes between calls. What is the probability that the time between calls will be less than 1 minute for a randomly selected period?

Select one:

a. .44

b. .31

c. .39

d. .61

e. .07

3) The time between customer service calls to a computer-repair hotline follows an exponential distribution with an expectation of 2 minutes between calls. We collect calls for 40 minutes at random times during the month (a sample of size n=40). What is the probability that the mean of our sampling distribution will be greater than 2.2 minutes?

Select one:

a. .17

b. .26

c. .37

d. .68

e. .78

Answer 1