A math problem

Johnny goes to the dentist.  The dentist tells Johnny that his portion of the bill is $137.49.  Johnny asks the dentist if that $137.49 will be submitted as part of the claim to the insurance company so Johnny can get reimbursed for it.  The dentist says yes.

Johnny gets the statement from the insurance company.  It shows the dentist charged the insurance company a total of $177.  The insurance company paid 80% of the bill.  Johnny does some quick math.  $177 + $137.49 = $314.49  If the dentist submitted that amount to the insurance company Johnny would have been responsible for $63, not $137.49. 

Johnny will be calling the dentist today and asking them to pull out their calculators so he can go over this math problem with them. Johnny really gets angry when people try to screw him.