All things being equal (lane conditions, good health, etc..) for our contest, we have Joe and Fred who bowl in the same league. They have averages which have been created by the last 2 years of games, which is around 250 games for each. Let's say for arguments sake that their averages are spot on.
Joe has an average of 190, Fred has an average of 210.
What's an accurate vig-free ML for a standard one game/10 frame contest between the two?