Question

The following table shows the time in various cities when it is 4:00 a.m. in New York.

New York
4:00 a.m.
San Juan
5:00 a.m.
Buenos Aires
6:00 a.m.
Dublin
9:00 a.m.
Rome
10:00 a.m.
Istanbul
11:00 a.m.
Saint Petersburg
12:00 p.m.
Beijing
5:00 p.m.
Osaka
6:00 p.m.

If a flight between two of these cities leaves at 1:30 p.m. on Friday (local time), flies for 16 hours and 30 minutes, and arrives at 2:00 a.m. Saturday (local time), which of the following pairs of cities could the flight go between?
a.
New York and Rome
b.
Saint Petersburg and Beijing
c.
Dublin and San Juan
d.
Osaka and Istanbul


Please select the best answer from the choices provided

A
B
C
D

Answer 1

C

Reason: Let tz(city) be hours offset from New York given by the table (San Juan +1, Dublin +5, etc.). If departure is 13:30 and flight time is 16.5 h, arrival local time 02:00 next day gives
13.5 + 16.5 + (tz_arrival − tz_departure) = 26.0,
so tz_arrival − tz_departure = −4. The only listed pair with a 4‑hour difference (arrival 4 hours behind departure) is Dublin (+5) to San Juan (+1), since 1 − 5 = −4.