Answer :
The cost that John has to finance is the boat price minus the down payment:
$17,000 - $2,500 = $14,500
That amount is paid by John with a finance cost to add of $4,900 during 60 months.
$14,500 + $4,900 = $19,400 / 60 months = $323,34
Then the monthly payment is: $323,34