In: Statistics and Probability
The diameter of a brand of tennis balls is approximately normally distributed, with a mean of 2.63 inches and a population standard deviation of .03 inch. If you select a random sample of 9 tennis balls, (a) What is the standard error of the mean? (b) What is the probability that the sample mean is less than 2.61 inches? (c) What is the probability that the sample mean is between 2.62 and 2.64 inches? (d) Between what two values symmetrically distributed around the mean are 60% of the values?