In a certain code language, ‘A + B’ means ‘A is the mother of B’; ‘A − B’ means ‘A is the brother of B’; ‘A x B’ means ‘A is the sister of B’ and ‘A ÷ B’ means ‘A is the daughter of B’. Based on the above, if ‘J + K ÷ L − T x R’, then how is J related to L?

Correct — B. Decode the chain left to right, one symbol at a time.

J + K: J is the mother of K.
K ÷ L: K is the daughter of L.
L − T: L is the brother of T, so L is male.

K has J as mother and L as parent, and L is male, so L is K's father.

J and L are therefore the two parents of one child, which makes J the wife of L — option (b).

Why the others are wrong

• (a)
  Husband’s sister — Husband's sister makes J a sister-in-law standing outside the marriage. The chain puts J and L in it, as K's mother and K's father.
• (c)
  Father’s sister — Father's sister puts J one generation above L. J is K's mother and L is K's father, so the two stand on the same generation, not on different ones.
• (d)
  Sister — Sister is what the × symbol codes, and J is never linked by ×. J's only link is J + K, which fixes her as K's mother.

Symbol-coded relations are solved as a drawing, not as a sentence.

Take one symbol at a time, left to right, and put each person on a family tree with the generation marked. Then mark gender wherever a symbol reveals it — mother, daughter and sister are female; brother is male.

The asked relation usually needs one gender fact that comes from a link you might think is decoration. Here it is L − T, which is the only thing making L male rather than female.

Key facts

• The codes in this question: + is mother of, − is brother of, × is sister of, ÷ is daughter of.
• L − T fixes L as male, which is what separates wife from husband.
• Two people who are the mother and the father of the same child are read as spouses in SSC's blood-relation questions.

Common traps

• Resolving the chain right to left, which reverses every parent-child link.
• Skipping L − T and leaving L's gender open, after which husband and wife are indistinguishable.
• Spending time on T × R, which says nothing about J or L.

No directly related past PYQ was found.