How are these numbers calculated?

Big Games

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

Week of 8/23100.0*Average seed
Rabbitohs 28 Bulldogs 20 +0.3
Storm 64 Eels 4 -0.1
Week of 8/30100.0*Average seed
Tigers 18 Rabbitohs 32 +0.3
Sea Eagles 28 Storm 8 +0.1
Roosters 22 Titans 30 +0.1
Week of 9/5100.0*Average seed
Rabbitohs 12 Roosters 24 -0.1
Games Above .500
Chance Will Make Playoffs