The facts are: A fast food chain claims that a large order of french fries has 540 calories. To test the claim that the true mean is actually higher, a sample of 15 large orders of french fries is taken. The sample mean is x-bar = 560 and the sample standard deviation is s = 21. How would I calculate what a 95% confidence interval is for the mean number of calories for all fries? I believe the mean number of calories for all large orders of fries is 540. What is the correct procedure too follow to calculate the interval?