Excel Skills Demonstration * B C D Excel skills E F G H K 1 The daily sales of Burger Baby restaurants follow the normal distribution with a standard deviation of $4000. 2 3 a. 4 A sample is taken of 50 restaurants and the average sales were $40,000/day. What is the 99% confidence interval for the average restaurant sales? Answer 5 6 7 8 9 10 11 b 12 What is the probability that the average sales are really $36,000 or less per day? Assume the actual population average is $40,000 per day Answer 13 14 15 16 17 18 19 20 21 22 23 24 A sample of the sales at 50 Haute Dog restaurants is taken and the sample mean is $30,000 per day with a sample standard deviation of $2000. The population standard deviation is not known. 25 26 a What is the 90% confidence interval for the daily sales at all restaurants. Answer 27 28 29 30 31 32 33 What is the probability that the average sales are really $32,000 or more per day? Assume that the population average is $30,000 per day and the std. Deviation is $2k. Answer 34 35 36 M N P