Directions: Each of the questions below consists of a question and two…

2022

Directions: Each of the questions below consists of a question and two statements numbered I and II. You have to decide whether the data provided in the statements are sufficient to answer the question. Read all the statements and answer.

Seven persons A-G sit in a row facing north, but not necessarily in the same order. Who among the following sits exactly between B and E?

Statement I: C is the only immediate neighbour of G. F sits 2nd to the left of B. E sits three places away from A.

Statement II: D sits 3rd to the left of B but does not sit at any extreme end. C sits 2nd to the right of A. B and G are not immediate neighbours.

  1. A.

    If the data in statement I alone are sufficient

  2. B.

    If the data in statement II alone are sufficient

  3. C.

    If the data either in statement I alone or statement II alone are sufficient to answer

  4. D.

    If the data given in both I and II together are not sufficient

  5. E.

    If the data given in both the statements I and II together are necessary to answer

Show answer & explanation

Correct answer: E

Concept

In a data-sufficiency problem you do not have to find the final answer outright; you only judge whether the given statements pin down a single, definite answer to the question asked. A statement is 'sufficient' only if every arrangement it allows yields the same answer. Test each statement alone first; combine them only if neither alone settles the question.

Application

Question asked: who sits exactly between B and E (the person at the equidistant midpoint of B and E) in a north-facing row of seven, A-G.

Statement I alone:

  1. C is the only immediate neighbour of G, so G is at an extreme end with C beside it; F is 2nd to the left of B; E is three places from A.

  2. These clues still allow several valid rows (for example F A B D E C G and G C F A B D E).

  3. Across those rows the midpoint of B and E comes out differently - sometimes D, sometimes another person, sometimes no equidistant midpoint at all.

  4. Because different valid rows give different answers, Statement I alone is not sufficient.

Statement II alone:

  1. D is 3rd to the left of B and not at an end; C is 2nd to the right of A; B and G are not neighbours.

  2. Many rows still satisfy this (for example A G C D E F B, F D E A B C G, G D F A B C E).

  3. The person at the B-E midpoint varies across these rows, so Statement II alone is not sufficient.

Both statements together:

  1. Apply every clue from I and II at once. The only row satisfying them all simultaneously is E D F A B C G.

  2. With one fully fixed arrangement the question is now answerable: E is in seat 1 and B is in seat 5, so the person at their equidistant midpoint (seat 3) is F.

  3. Thus the answer to the underlying seating question is F - reachable only after both statements are combined.

Cross-check

Neither statement alone narrows the row to one, so neither alone fixes who sits between B and E. The two statements together leave exactly one valid row, which determines the answer. Hence the data are sufficient only when both statements are used together.

Result

The data given in both statements I and II together are necessary to answer the question.

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