How are these numbers calculated?

Big Games

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

Week of 4/3100.0*Chance in playoffs100.0*Average seed
Libertad 2 Nacional 1 In
Alianza Lima 1 Vasco da Gama 2 -5.0
Week of 4/10100.0*Chance in playoffs100.0*Average seed
Alianza Lima 1 Libertad 2 +0.3
Nacional 0 Vasco da Gama 1 -0.3
Week of 4/17None
Chance Will Make Playoffs