If A + B means B is the brother of A; A x B means B is the husband of A; A - B…
2023
If A + B means B is the brother of A; A x B means B is the husband of A; A - B means A is the mother of B and A % B means A is the father of B, which of the following relations shows that Q is the grandmother of T ?
- A.
Q - P + R % T
- B.
P x Q % R - T
- C.
P x Q % R + T
- D.
P + Q % R - T
Show answer & explanation
Correct answer: A
Concept: In coded blood-relation puzzles, each symbol stands for a fixed relation with a fixed gender — mother/father links are gender-specific, while sibling and spouse links carry a relation sideways within the same generation. To show that one person is another's grandmother, the coding must chain two generations downward through a common relative: one link placing the person as a mother (of that relative, or of that relative's sibling), and a second link placing that relative as a parent of the target — with every intermediate link keeping the person's gender female throughout.
Applying this to Q - P + R % T:
Q - P → Q is the mother of P.
P + R → R is the brother of P, so R and P share the same mother; Q is therefore also the mother of R.
R % T → R is the father of T.
Chaining steps 2 and 3: Q (R's mother) and R (T's father) place Q two generations above T through R, with Q remaining female throughout the chain.
Cross-check: the '-' symbol appears only once here (Q - P), directly confirming Q as female from the very first link; the sibling link that follows (P + R) then carries that same maternal role over to R without introducing any male-only symbol for Q, so Q's gender stays female across the whole chain — satisfying the grandmother (rather than grandfather) requirement the question asks for.
Hence, Q - P + R % T is the coding that establishes Q as the grandmother of T.