In: Statistics and Probability
4. Sampling and Sampling Distributions
In the most recent hearing on Highway safety at the New York City Council hearings, it was determined that the average travels 1,123 miles per month. Assume the population standard deviation is 341 miles per month. Determine the interval that will contain 95% of the sample means for the sample size of
a. 30 drivers
b. 45 drivers
c. Explain the difference in these probabilities
a)
The interval is (1000.9747, 1245.0253)
b)
The interval is (1017.323, 1228.677)
c) We can conclude that, as the sample size increases, the width of the interval decreases.