Question

What is the time difference between New York and London?
I. The departure time at New York is exactly 9.00 a.m. local time and the arrival time at London is at 10.00 a.m. local time.
II. The flight time is 5 hours.

• A. If the question can be answered with the help of statement I alone.
• B. If the question can be answered with the help of statement II alone.
• C. If both the statement I and statement II are needed to answer the question.
• D. If the question cannot be answered even with the help of both the statements.

Hint:

Always align time zone problems using the format: Arrival = Departure + Duration + Time Difference.

Answer 1

The Correct Option is C

From Statement I: Departure = 9:00 a.m. (NY Time)
Arrival = 10:00 a.m. (London Time) Without knowing the duration of the flight, we cannot determine the time difference. From Statement II: Flight time = 5 hours
But we don’t know departure or arrival time zones, so this alone is also not enough. Combine both: If flight duration is 5 hours, and the clock difference is such that 9:00 a.m. departure reaches 10:00 a.m. London time, then London is 4 hours ahead. \[ \text{Arrival time (London)} = \text{Departure time (NY)} + \text{Flight Time} + \text{Time Difference} \] \[ 10 = 9 + 5 + \text{Time Difference} \Rightarrow \text{Time Difference} = -4 \Rightarrow \text{London is 4 hours ahead} \]