How are these numbers calculated?

Big Games

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

Week of 10/17100.0*Average seed
Sounders 0 Real Salt Lake 0 -0.3
Week of 10/20100.0*Average seed
Sounders 3 FC Dallas 1 +0.2
Earthquakes 2 Galaxy 2 -0.0
Week of 10/28100.0*Average seed
Galaxy 1 Sounders 0 -0.5
Chance Will Make Playoffs