In a certain code language, A + B means ‘A is the son of B’, A − B means ‘A is the wife of B’, A × B means ‘A is the brother of B’ and A ÷ B means ‘A is the mother of B’. Based on the above, how is T related to P if ‘P − M + R ÷ T × S’?

Correct — B. Read the string left to right, one link at a time.

P - M: P is the wife of M.
M + R: M is the son of R.
R / T: R is the mother of T.
T x S: T is the brother of S, which fixes T as male.

R is the mother of both M and T, so M and T are brothers, and P is married to M.

T is therefore P's husband's brother -> option (b).

Why the others are wrong

• (a)
  Sister — T is the brother of S, so T is male. Sister is out before the chain is even finished.
• (c)
  Brother’s wife — Brother's wife needs T to be female and married to a brother of P. T is male, and T's only link to P runs through M, P's husband.
• (d)
  Brother — T is P's husband's brother, not P's own. Nothing in the string makes P a child of R.

A symbol-coded relation string is read strictly left to right, each symbol joining only the name just before it to the name just after it.

Build the family as you go. Two people with the same mother are siblings, and marriage links you to your spouse's brothers and sisters, not to your own.

A term's gender often arrives later than the term does. Here T is known to be male only because T is the brother of S, at the last link of the string.

Key facts

• In this legend A - B means A is the wife of B, and A / B means A is the mother of B.
• R is the mother of M and of T, which makes M and T brothers.
• T is male because the string states T is the brother of S.

Common traps

• Reading the string as a whole instead of link by link
• Taking T to be female and answering sister or brother's wife
• Calling T a brother of P when the link runs through P's husband

No directly related past PYQ was found.