The management of a supermarket wanted to investigate whetherthe male customers spend less money on average than femalecustomers. A sample of 22 male customers who shopped at thissupermarket showed that they spent an average of $73 with astandard deviation of $17.50. Another sample of 20 female customerswho shopped at the same supermarket showed that they spent anaverage of $87 with a standard deviation of $14.40. Assume that theamounts spent at this supermarket by all male and female customersare normally distributed with unequal and unknown populationstandard deviations.
a.) Construct a 90% confidence interval for the differencebetween the mean amounts spent by all male and all female customersat this supermarket.
b.) Using the 2.5% significance level, can you conclude that themean amount spent by all male customers at this supermarket is lessthan that by all female customers?
c) Interpret the conclusion obtained in part b.
