How are these numbers calculated?

Big Games

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

Week of 4/6None
Week of 4/13100.0*Chance in playoffs100.0*Average seed
Universidad San Martin 0 Once Caldas 2 +51.5
Libertad 2 San Luis 0 +7.2
Week of 4/20None
Chance Will Make Playoffs