How are these numbers calculated?

Big Games

How we did last week and who we should root for this week.   Explain

Week of 10/3100.0*Chance in playoffs100.0*Average seed
Spruce Grove 52 Jasper Place 27 +0.4
Week of 10/10100.0*Chance in playoffs100.0*Average seed
Jasper Place 63 Ross Shep 10 Out
-0.0
Bev Facey 31 Harry Ainlay 28 +0.4
Salisbury 21 AOB 14 +0.1
Week of 10/17None
Games Above .500
Chance Will Make Playoffs