The manager of a department store wants to determine what proportion of people who enter the store use the store's credit cards for their purchases.

The manager of a department store wants to determine what proportion of people who enter the store use the store's credit cards for their purchases.  What size sample should he take so that at 95% confidence the error will not be more than 5.5%?

The manager of a department store wants to determine what proportions of people whoenter the store use the store's credit cards for their purchases. What size sample should hetake so that at 95%...