Suppose you take out a 30 year mortgage for $ 250000 at 7.75% interest. The monthly payments on this loan are $ 1791.03.

If you pay an extra 20% per month on your mortgage, how soon will you pay off the loan? New length in years = 18.0 years

How much will you save in interest by making the extra payments? Saving = $180535.824

If you put $ 1791.03 per month into an annuity earning 10.5% interest compounded monthly for the remaining time on your original loan, how much money will you have at the end of the original 30 years? Extra savings = ?