It is unlikely that Bernhard is yellow. It is highly likely that Greg is a rhino. It is almost certain that Julius is green. There is little chance that if either 'Greg is a rhino' or 'Bernhard is yellow' but not both then Sandra left the milk. There is little chance that if 'Greg is a rhino' or 'Julius is green' or both then Lily is green. Chances are about even that if 'Greg is a rhino and Julius is green' then John got the football.
Chances are about even that 'Greg is a rhino and John got the football'.
Chances are about even that 'Greg is a rhino and John got the football'.
It is almost certain that 'Greg is a rhino and John got the football'.

  and(A,B) :- A,B.
  or(A,B) :- A;B.
  nand(A,B) :- not(and(A,B)).
  nor(A,B) :- not(or(A,B)).
  xor(A,B) :- or(A,B), nand(A,B).

  %hop0
  0.2::factA.
  0.9::factB.
  0.95::factC.
  %hop1
  0.1::factX:-xor(factB,factA).
  0.1::factY:-or(factB,factC).
  0.5::factZ:-and(factB,factC).

  %hop2
  conclusion:-and(factB,factZ).

  query(conclusion).
  
'Greg is a rhino and John got the football'.