If A + B means A is the brother of B, A - B means A is the sister of B, and A × B means A is the father of B, what is the relationship of C to D if C + D and D - C are true?
In a coded relationship, if M + N means M is the sister of N, M - N means M is the brother of N, and M × N means M is the mother of N, what is the relationship of O if M + O × N?
In a coded relation, if P * Q means P is the mother of Q, P ÷ Q means P is the father of Q, and P + Q means P is the sister of Q, what is the relation of R if P * R ÷ Q?