How are these numbers calculated?

Big Games

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

Week of 8/11100.0*Chance in playoffs100.0*Average seed
StevesPizza 3 TeamAmerica 6 +4.3
TheMightyPylons 4 DC 6 +3.1
Week of 8/18100.0*Chance in playoffs100.0*Average seed
DC 7 TeamAmerica 5 +29.2
+0.3
StevesPizza 3 TheHawks 2 Out
-0.1
Week of 8/25None
Points
Chance Will Make Playoffs