How are these numbers calculated?

Big Games

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

Week of 4/15100.0*Chance in playoffs100.0*Average seed
Mill Creek High 2 Peachtree Ridge 0 -19.7
-0.9
Mountain View H 0 Habersham Centr 4 -3.7
-0.2
Duluth High Sch 2 Meadowcreek Hig 0 +3.1
North Gwinnett 0 Mill Creek High 1 -0.1
-0.1
Week of 4/18100.0*Chance in playoffs100.0*Average seed
Collins Hill Hi 0 Peachtree Ridge 3 In
+1.4
Peachtree Ridge 2 Norcross High S 1 +25.1
+1.2
Habersham Centr 1 Duluth High Sch 2 +6.3
+0.1
Norcross High S 2 Duluth High Sch 5 -0.1
Points
Chance Will Make Playoffs