Data Sufficiency — Departure time today: At what time did the train leave today? Statements: I. The train normally leaves on time. II. The scheduled departure is at 14:30.
Correct Answer: Neither I nor II is sufficient
Introduction / Context:The task is to determine today’s actual departure time. Data sufficiency asks whether the statements individually or together allow a definite answer without extra assumptions (like “today was routine”).
Given Data / Assumptions:
- I: The train “normally” leaves on time (a general tendency, not a guarantee for today).
- II: The timetable lists scheduled departure at 14:30.
- We cannot infer today’s punctuality unless explicitly stated.
Concept / Approach:Distinguish between normative information (usually, normally) and fact for the specific day in question. Schedules provide intended times; actual operations can differ due to delays or advancements.
Step-by-Step Solution:Statement I only says “normally on time.” It does not say “today it left on time.”Statement II only provides the scheduled time 14:30.Even when combined, we still lack confirmation that today adhered to the schedule.Therefore, we cannot determine the exact departure time for today.
Verification / Alternative check:If Statement I had said “today it left on time,” then with II we could conclude 14:30. But “normally” is not “today.” Hence insufficiency remains even after combining.
Why Other Options Are Wrong:
- I alone: Insufficient—no specific confirmation for today.
- II alone: Insufficient—timetable ≠ actual.
- Either or both: Still cannot fix today’s actual time.
Common Pitfalls:
- Equating “normally” with “always” or “today.”
- Assuming punctuality without explicit evidence.
Final Answer:Neither I nor II is sufficient