How are these numbers calculated?

Big Games

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

Week of 2/8100.0*Pres Trophy100.0*Average seed
Rock Ridge/Heritage 7 Dominion/Potomac Falls 3 +18.4
+0.4
Yorktown 1 Langley 1 +2.1
Centreville/Fairfax 1 Chantilly 11 -1.6
-0.0
If winner is:HomeTieAway
Week of 2/22100.0*Pres Trophy100.0*Average seed
Kettle Run/Liberty vs Rock Ridge/HeritageNoNo+21.3
-0.5-0.5+0.2

What If

Chances based on how well the Rock Ridge/Heritage finish out the regular season.   Explain

100100100100100100100100100100100100100100100100100100100100100100100
If finish:Chance inPresChance will finish regular season at seed
TPW-L-TplayoffsTrophy1234567891011121314151617181920212223Count
181-0-0In70.3%70302,252,087,632
16-17InNo100981,710,362*
Total:In49.0%49513,233,797,994

* Row combines multiple less frequent records.

Games Above .500
Chance Will Make Playoffs