How are these numbers calculated?

Big Games

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

Week of 4/10100.0*Chance in playoffs100.0*Average seed
Red Sox 361 Indians 260 +15.4
+1.3
Nationals 169 Twins 250 -1.3
-0.1
Tigers 310 Phillies 195 -0.6
-0.0
White Sox 200 Americans 164 +0.5
Blue Jays 271 Brewers 305 +0.5
Week of 4/17100.0*Chance in playoffs100.0*Average seed
Rays 194 Red Sox 226 +13.1
+1.0
Twins 232 Pirates 218 -4.0
-0.2
Phillies 225 Blue Jays 294 -2.4
-0.1
Americans 217 Tigers 230 +1.0
-0.0
Brewers 298 White Sox 277 -0.4
-0.0
Indians 192 Nationals 281 -0.0
Week of 4/24100.0*Chance in playoffs100.0*Average seed
Red Sox 236 Pirates 187 In
+1.4
Brewers 257 Americans 351 +6.9
+0.2
Blue Jays 251 Tigers 123 -5.6
+0.0
Indians 266 Twins 250 +4.4
+0.2
Games Above .500
Chance Will Make Playoffs