FreddieMac reports that the average rate on a 30-year fixed-rate mortgage is 3.92% as of January 2012. This is down from 4.76% in January 2011 and 5.03% in January 2010. If you have a $230,000, 5%, 30-year mortgage, how much interest will you save if you refinance your loan at 3.5% for 15 years?

Don't Copy it from Chegg, Or I will report.