Random variables

Customers can replace 1, 2, 3, or 4 tires at a time for their vehicle at Thrifty Tires, a nationwide tire shop chain. For customers who have had their tires replaced at Thrifty Tires, the mean number of tires replaced is u = 3.83, with a standard deviation of 6 = 1.37. Suppose that we will take a random sample of n = 6 tire replacement orders. (Each order gives the number of tires being replaced.) Let x represent the sample mean of the 6 tire replacement orders. Consider the sampling distribution of the sample mean x. Complete the following. Do not round any intermediate computations. Write your answers with two decimal places, rounding if needed. (a) Find u- (the mean of the sampling distribution of the sample mean). H- = [ X ? (b) Find o- (the standard deviation of the sampling distribution of the sample mean)