How are these numbers calculated?

Big Games

How we did yesterday and who we should root for today.   Explain

Tuesday, 4/30100.0*Average seed
Southern 10 Broadneck 15 +0.7
Old Mill 12 Glen Burnie 1 -0.1
North County 2 Annapolis 12 -0.1
Meade 1 Northeast 14 -0.1
Friday, 5/3None
Games Above .500
Chance Will Make Playoffs