In a coded relation, if P × Q means P is the mother of Q, P ÷ Q means P is the son of Q, and P + Q means P is the sister of Q, what is the relationship of R if P × R ÷ Q means P is the mother of R and R is the son of Q?
If X - Y means X is the sister of Y, Y + Z means Y is the brother of Z, and Z × W means Z is the father of W, what is the relationship of W to X if the expression is X - Y + Z × W?