How are these numbers calculated?

Big Games

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

Week of 1/31100.0*Average seed
McLean 5 Briar Woods 8 -0.1
Broad Run 5 Dominion/Potomac Falls 4 +0.1
Week of 2/7100.0*Average seed
Patriot 5 Yorktown 1 -0.3
Briar Woods 5 Stone Bridge 6 +0.2
Week of 2/14None

What If

Chances based on how well the Yorktown finish out the regular season.   Explain

If finish:Chance inChance will finish regular season at seed
Games Above .500
Chance Will Make Playoffs