# A random sample of 20 purchases showed the amounts in the table (in $). The mean is $50.03 and the standard deviation is $18.67. a) Construct a 90% confidence interval for the mean purchases of all customers, assuming that the assumptions and conditions for the confidence interval have been met. b) How large is the margin of error? c) How

## This problem has been solved!

Do you need an answer to a question different from the above? Ask your question!

**Related Book For**

## Business Statistics

3rd edition

Authors: Norean Sharpe, Richard Veaux, Paul Velleman

ISBN: 978-0321925831