Question: Students who graduated from college in 2010 owed an average
Students who graduated from college in 2010 owed an average of $25,250 in student loans (New York Times, November 2, 2011). An economist wants to determine if average debt has changed. She takes a sample of 40 recent graduates and finds that their average debt was $27,500 with a standard deviation of $9,120. Use a 90% confidence interval to determine if average debt has changed.
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