The average cost of a gallon of regular unleaded fuel at a g

The average cost of a gallon of regular unleaded fuel at a gas station in Auguat 2010 was $2.78. Assume that the standard deviation of such costs is $0.15. Suppose that a random sample of n = 100 gas stations is selected from the population and the cost per gallon of regular unleaded fuel is determined for each. Consider x?, the sample mean cost per gallon.

a) Calculate

Solution

The average cost of a gallon of regular unleaded fuel at a gas station in Auguat 2010 was $2.78. Assume that the standard deviation of such costs is $0.15. Suppose that a random sample of n = 100 gas stations is selected from the population and the cost per gallon of regular unleaded fuel is determined for each. Consider x?, the sample mean cost per gallon.

a) Calculate