What equation(s) do I use to go about solving this problem and what numbers do I plug in where? I am lost.

( 4 . ) 10 Points - One year ago you bought a home and got a $250 090 30 year , 7 5% fixed -rate mortgage loan Today , mortgage interest rates have plunged and new 30 year fixed rate mortgages are now available at 5.5 % If you refinanced it would cost you ! $3 500 in fees to get this new mortgage Assume that the mortgage balance is still equal to the original amount ie $250,000 If you refinanced your mortgage at the new lower rate , how long ( ignoring the time value of money ) would it take you to recover the fees that you incurred in efinancing your mortgage