A recent study found that consumers are making average monthly debt payments of $983 (Experian.com, November 11, 2010). The accompanying table shows a portion of average debt payments for 26 metropolitan areas. The complete data set, labeled Debt_Payments, can be found on the text website. Use Excel to construct 90% and 95% confidence intervals for the population mean. Comment on the width of the interval.
City Debt Payments
Washington, D.C.. $1,285
Seattle........ 1,135
:.......... :
Pittsburgh....... 763