Ram is smarter than Mohan. Rakesh is smarter than Ramu and Mohini is smarter…
2025
Ram is smarter than Mohan. Rakesh is smarter than Ramu and Mohini is smarter than Rakesh. Which of the following is a set(s) of additional information that can determine the smartest person?
(I) Mohini is smarter than Ram and Mohan is smarter than Rakesh.
(II) Mohan is smarter than Mohini.
(III) Ram is smarter than Mohini.
- A.
Only (II)
- B.
Only (III)
- C.
Either (I) or (II)
- D.
None of these
Show answer & explanation
Correct answer: D
CONCEPT: In a sufficiency puzzle about "who ranks highest", a piece of additional information is sufficient exactly when it lets one named person be shown - directly or by chaining (transitivity) through the given "smarter than" facts - to be smarter than every other named person; a full linear ranking of everyone is not required, only that one person dominate all the rest.
Given: Ram > Mohan. Rakesh > Ramu. Mohini > Rakesh (so Mohini > Rakesh > Ramu).
Evaluate (I): Mohini > Ram and Mohan > Rakesh. Chaining Mohini > Ram > Mohan with Mohini > Rakesh > Ramu gives Mohini > Ram > Mohan > Rakesh > Ramu, so Mohini is shown smarter than every other person.
Evaluate (II): Mohan > Mohini. Chaining Mohan > Mohini > Rakesh > Ramu with Ram > Mohan gives Ram > Mohan > Mohini > Rakesh > Ramu, so Ram is shown smarter than every other person.
Evaluate (III): Ram > Mohini. Chaining Ram > Mohini > Rakesh > Ramu (so Ram is transitively above Rakesh and Ramu too) with the already-given Ram > Mohan shows Ram smarter than every other person as well - even though Mohan's relation to Mohini/Rakesh/Ramu stays unknown, that does not matter once Ram already dominates all four individually.
So (I), (II), and (III) are each individually sufficient on their own to determine the smartest person (Mohini via (I); Ram via (II) or (III)).
CROSS-CHECK: none of the three specific characterizations offered - 'Only (II)', 'Only (III)', 'Either (I) or (II)' - is complete, since each of them leaves out at least one statement that is also independently sufficient (leaving out (I) and/or (III)). Since the true characterization ('(I), (II), and (III) are all individually sufficient') is not one of the listed positive choices, the correct choice is the catch-all option that says the true answer is not among the specific characterizations listed.