In a certain code language,P + Q means 'P is the son of Q', P & Q means 'P is…
2025
In a certain code language,
P + Q means 'P is the son of Q',
P & Q means 'P is the husband of Q',
P % Q means 'P is the mother of Q',
and P # Q means 'P is the sister of Q'.
Which of the following mean(s) that F is the father of T?
(I) R % F & S % N & T
(II) R % F & S % N # T
(III) R # F & S % N # T
(IV) R % F + S # N # T
Answer: D. Both II and III — Concept — In a coded-relationship chain every symbol relates only the two letters standing immediately on either side of it, and the chain is read from left…
- A.
Only I
- B.
Both I and III
- C.
Only III
- D.
Both II and III
Show answer & explanation
Correct answer: D
Concept — In a coded-relationship chain every symbol relates only the two letters standing immediately on either side of it, and the chain is read from left to right. Calling one person the father of another needs two independent facts to hold at the same time: that person has to be male, and the other has to be his child. Maleness comes from a male-specific link such as husband or son. Parenthood can be reached directly through a parent link, or indirectly through marriage, because the husband of a woman who is the mother of a child is that child's father; and since siblings share the same parents, a parent of one sibling is a parent of the other.
So two things have to be located inside a chain before F can be called the father of T:
a link that marks F as male, which here can only be the husband link or the son link;
a route from F to T that ends in parenthood, either because F is given directly as a parent of T, or because F is the husband of a woman who is the mother of T or of a sister of T.
Applying it — Each statement is decoded link by link, and the last column records what the decoded chain makes F to T.
Statement | Links, read from left to right | What the chain makes F to T |
|---|---|---|
I. R % F & S % N & T | R is the mother of F; F is the husband of S; S is the mother of N; N is the husband of T | F is the husband of N's mother, so F is the father of N; T is the wife of N, which makes F the father-in-law of T |
II. R % F & S % N # T | R is the mother of F; F is the husband of S; S is the mother of N; N is the sister of T | N is a sister of T, so N and T are siblings and S is the mother of T as well; F is the husband of S and is therefore the father of T |
III. R # F & S % N # T | R is the sister of F; F is the husband of S; S is the mother of N; N is the sister of T | the same core chain: S is the mother of T, so F, being her husband, is the father of T; the link joining R to F adds nothing |
IV. R % F + S # N # T | R is the mother of F; F is the son of S; S is the sister of N; N is the sister of T | F is marked as a son and sits one generation below S, N and T; S is a sister of N and N is a sister of T, so T is a sibling of F’s mother, that is F’s maternal aunt or uncle, and in no case his child |
Cross-check — Statements II and III carry the same operative sub-chain, F & S % N # T: F is the husband of S, S is the mother of N, and N is the sister of T. That sub-chain is precisely the indirect route to fatherhood set out above, and the point where those two statements differ, R as the mother of F against R as the sister of F, lies outside it and changes nothing. The remaining two break at an identifiable link instead: in I the final link is a husband link, so T arrives as a spouse rather than as a child, and in IV the second link marks F himself as a son.
The statements that mean F is the father of T are therefore II and III.