How are these numbers calculated?

Big Games

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

Week of 9/19100.0*Average seed
Clementi 3 Sengkang 1 -0.3
Geylang 5 Balestier 1 -0.1
Week of 9/26None
Week of 10/3100.0*Average seed
Balestier 2 SAFFC 4 -0.1
Points
Chance Will Win Championship