question archive The monthly closing stock prices (rounded to the nearest dollar) for Panera Bread Co
Subject:ManagementPrice: Bought3
The monthly closing stock prices (rounded to the nearest dollar) for Panera Bread Co. for the first six months of 2010 are reported in the following table.
Month |
Closing stock price |
January 2010 |
$71 |
February 2010 |
73 |
March 2010 |
76 |
April 2010 |
78 |
May 2010 |
81 |
June 2010 |
75 |
a. Calculate the sample mean and the sample standard deviation.
b. Compute the 90% confidence interval of the mean stock price of Panera Bread Co., assuming that the stock price is normally distributed.
c. What happens to the margin of error if a higher confidence level is used for the interval estimate?