The queuing time at an airline check-in has a population mean h = 13 minutes and variance o2 = 16 minutes2. Suppose that n = 27 passengers were randomly selected from this population. They were interviewed and reported the queued times. Let x̄ defines the sample mean of n observations. Answer the followings:
a) Define your random variable X.
b) Define the sampling distribution of sample mean (indicate a reason and give the name of the distribution, the parameters and sketch it.
c) What is the probability that a sample mean is at most 11 minutes. Please skecth the problem and show all details of your answer.
d) Suppose that for n = 27 passengers, the sample mean is observed as x̄= 10 minutes. Based on part c, can we claim that the population mean queuing time is less than 13 minutes.
e) Construct a 95% acceptance region for sample mean of queing time (i.e., u + za x f) Interpret the result obtained in parte and skecth the control chart.
The queuing time at an airline check-in has a population mean h = 13 minutes and variance o2 = 16 minutes2. Suppose that n = 27 passengers were randomly selected from this population. They were interviewed and reported the queued times. Let x̄ defines the sample mean of n observations. Answer the followings:
a) Define your random variable X.
b) Define the sampling distribution of sample mean (indicate a reason and give the name of the distribution, the parameters and sketch it.
c) What is the probability that a sample mean is at most 11 minutes. Please skecth the problem and show all details of your answer.
d) Suppose that for n = 27 passengers, the sample mean is observed as x̄= 10 minutes. Based on part c, can we claim that the population mean queuing time is less than 13 minutes.
e) Construct a 95% acceptance region for sample mean of queing time (i.e., u + za x f) Interpret the result obtained in parte and skecth the control chart.
