How are these numbers calculated?

Big Games

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

Week of 4/26100.0*Chance in playoffs100.0*Average seed
Cobreloa 2 San Lorenzo 0 -4.6
Week of 5/3100.0*Chance in playoffs100.0*Average seed
San Lorenzo 0 Once Caldas 1 -22.8
Chivas Guadalajara 3 Cobreloa 1 In
Week of 5/10None
Chance Will Make Playoffs