A savings and loan association needs information concerning the checking account balances of its local customers. A random sample of 14 accounts was checked and yielded a mean balance of $664.14 and a standard deviation of $297.29. Find the following. a) Assuming that these 14 accounts can be considered a random sample, construct a 95% confidence interval for the true mean checking account balance for local customers. (Assume that the normal probability plot doesn't exhibit major departure from the normality assumption.) b) Interpret in words as it pertains to this situation the confidence interval found in part a). c) If you lower the confidence level to 90% would you get a more precise estimate or a less precise estimate? Explain.

A savings and loan association needs information concerning the checking account balances of its local customers. A random sample of 14 accounts was checked and yielded a mean balance of $664.14 and a standard deviation of $297.29. Find the following. a) Assuming that these 14 accounts can be considered a random sample, construct a 95% confidence interval for the true mean checking account balance for local customers. (Assume that the normal probability plot doesn't exhibit major departure from the normality assumption.) b) Interpret in words as it pertains to this situation the confidence interval found in part a). c) If you lower the confidence level to 90% would you get a more precise estimate or a less precise estimate? Explain.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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