Walter owns a curio shop in downtown. Inventory records suggest that a particular curio brand is quite popular. Data indicates that on average other...

Walter owns a curio shop in downtown. Inventory records suggest that a particular curio brand is quite popular. Data indicates that on average other curio shops sells 12.2 pounds per day of that brand. Walter in attempt to find out how his sales compares with this average, took a sample of 250 days and found that the average sales was 41.3 pounds and standard deviation of 2.75 pounds. He does not know whether daily sales are normally distributed or not. What does 90% confidence interval reveal about Walter’s average sales compared with other curio shops?