Direction: The following consists of a question and two statements numbered I…

2023

Direction: The following consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statements are sufficient to answer the question.

Seven persons from A to G are sitting in a linear row facing towards the north.

Who is sitting at the right end?

Statement I: B is second to the left of D, who is on the immediate right of A. C is third to the left of G, who is an immediate neighbour of B.

Statement II: A is on the immediate right of B. F, who does not sit at an extreme end is third to the left of B. G is third to the left of D.

  1. A.

    If the data either in statement I alone or in statement II alone is sufficient to answer the question.

  2. B.

    If the data in statement II alone is sufficient to answer the question, while the data in statement I alone is not sufficient to answer the question.

  3. C.

    If the data in statement I alone is sufficient to answer the question, while the data in statement II alone is not sufficient to answer the question.

  4. D.

    If the data in both statement I and II together are not sufficient to answer the question.

Show answer & explanation

Correct answer: C

In a data-sufficiency question, a statement is sufficient only when its clues fix the specific value being asked about — here, who sits at the right end — even if some other seats among the remaining people stay interchangeable.

Statement I:

  1. D is immediately right of A, so A sits directly to D's left.

  2. B is second to the left of D, leaving exactly one seat between B and D.

  3. G is an immediate neighbour of B; since A already occupies one of the two seats next to B, G must occupy the other, which places G third to the left of D.

  4. C is third to the left of G, which places C six seats to the left of D.

  5. C, G, B, A and D therefore occupy five seats stretching across the full width of the seven-seat row, so the two remaining people fill only the two seats between C and G — no seat is left to the right of D.

So Statement I alone fixes D at the right end, regardless of how the two remaining people are arranged between C and G.

Statement II:

  1. A sits immediately right of B, and F, who cannot take an extreme seat, sits third to the left of B.

  2. If B sits at the 4th seat from the left, F would land on the very first (extreme) seat, which the statement rules out — so B must sit at the 5th or 6th seat instead.

  3. If B sits at the 5th seat: A is at the 6th, F is at the 2nd, and placing G third to the left of D still allows two different outcomes among the leftover seats (1st, 3rd, 4th, 7th) — one puts D at the 4th seat and leaves the 7th seat for one of the two remaining people; the other puts D himself at the 7th seat.

  4. If B sits at the 6th seat: A is at the 7th, F is at the 3rd, and placing G third to the left of D again allows more than one outcome among the leftover seats (1st, 2nd, 4th, 5th) — but here A always ends up at the 7th seat.

So across these valid seatings the right end is occupied by D in one case, by A in another, and by one of the two remaining people in a third — Statement II alone does not fix a single occupant and is not sufficient.

Cross-checking the two: Statement I's clues chain into one seating with no ambiguity that touches the right end, while Statement II's clues admit multiple seatings that disagree on who sits there — confirming that only Statement I alone is sufficient.

Therefore, D is the person sitting at the right end, and this is established uniquely by Statement I alone; Statement II alone does not settle it.

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