Medical math

In my left hand is a bill from the doctor. In my left hand is a copy of the insurance company's processing of a claim for the same service.

The doctor's bill claims they sent the insurance company a bill for $140.

The insurance company, which provides an itemized list of the billed services, says they were billed $73.

The insurance company says they paid $25, because a) the doctor charged $20 for something not covered and b) overcharged for the rest.

The doctor claims he got $47.79. (Not counting the $50 copay for the visit.)

The doctor says I owe $10.46. Why exactly isn't clear, since his math isn't even in the ballpark. ($140 minus $47.79? Or even $73 minus $47.79?)

The insurance company doesn't say I owe anything, but if the $20 charge isn't covered, obviously that would be the likely amount.

So what do I do?

Write a check for $10.46 and go have a beer.