Ha,you're wrong as I did first.

The information is too less.But we can get the Ex V=83% .The no.1 if see no.2 and no.3 have same color,say white,different color
say black.2 and 3 can free,.. 3m+1 do the same thing,3m+2, 3m+2 can free,100 guess.So,66+ 34/2=83.