PGes = X(A)*P0(A) + (1-X(A))*P0(B)
PGes = X(A)*P0(A) + P0(B) -X(A)*P0(B)
PGes = X(A)(P0(A) - P0(B)) +P0(B)
PGes -P0(B) =X(A)(P0(A) - P0(B))
X(A)=(PGes -P0(B))/(P0(A) - P0(B))
PGes = X(A)*P0 (A)+X(B)*P0 (B)
PGes -(X(A)*P0 (A))=X(B)*P0 (B)
X(B)=(PGes -(X(A)*P0 (A))) /(P0 (B))