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
Vasco da Gama 0 Botafogo 3 +10.9
+0.3
Vasco da Gama 2 Friburguense 1 +9.4
+0.2
Botafogo 3 Olaria 0 +6.3
+0.2
Nova Iguacu 1 Volta Redonda 0 +3.7
+0.2
Week of 4/10100.0*Chance in playoffs100.0*Average seed
Botafogo 3 Friburguense 1 In
+0.2
Volta Redonda 0 Olaria 0 +0.1
Botafogo 4 Nova Iguacu 1 +0.1
Week of 4/21None
Points
Chance Will Make Playoffs