Assignment:
Question 1. Hockey-r-us" a store specializing in sales of hockey equipment, wants to find out the average age of all it's customers. A random sample 25 customers reveals an average age of 38 years, with a standard deviation of six years. Determine a 95% confidence interval of the average age of all customers.
Question 2. Refer to the question above. How large of a sample should be constructed to be 90% confident that the sampling error is one or less?
Provide complete and step by step solution for the question and show calculations and use formulas.