Checking my math with the brainiacs here. On the line
XYZ -220
ABC +200
the house advantage equals:
XYZ -220 = 5/11; converted to percentage as 11(100)/5+11 = 68.75%
ABC +200 = 2/1; converted to a percentage as 1(100)/2+1 = 33.33%
33.33% + 68.75% = 102.08%
meaning the book has a 2.08% overround built into this line.
Have I got this right?