On which floor of the building does G stay? (Building has five floors: 1, 2, 3, 4, 5.) I. Only the even-numbered floors are occupied and G does not stay on the second floor. II. G does not stay on an odd-numbered floor.
Verbal Reasoning
Data Sufficiency
Difficulty: Easy
Choose an option
Answer
Correct Answer: Statement I alone is sufficient; Statement II alone is not.
Explanation
Introduction / Context:We must uniquely identify G's floor in a five-floor building. Data Sufficiency asks whether each statement pinpoints a single floor for G without ambiguity.
Given Data / Assumptions:
- I: Only even floors are occupied; G is not on floor 2.
- II: G is on an even floor (i.e., not odd).
Concept / Approach:Enumerate feasible floors from each statement and check if a unique floor is forced.
Step-by-Step Solution:
1) From I: Occupied floors are {2, 4} only; since G is not on 2, G must be on 4. I alone is sufficient.2) From II: G is not on {1,3,5}; G could be on 2 or 4. II alone does not fix a unique floor.3) Therefore, answer type A holds.Verification / Alternative check:Check consistency: If only even floors are occupied, II is implied but weaker.
Why Other Options Are Wrong:
- B: II alone leaves two possibilities.
- C: Not either alone; only I suffices.
- D/E: Not applicable since I alone is already sufficient.
Common Pitfalls:Overlooking “only even-numbered floors are occupied,” which collapses the possibilities.
Final Answer:Statement I alone is sufficient; Statement II alone is not.