UPSC Prelims 2007 Q74: Geography – Astronomy & Earth - Sun System
Which one of the following cities does NOT have the same clock time as that of the other
cities at any given instant?
- (a) London (UK)
- (b) Lisbon (Portugal)
- (c) Accra (Ghana)
- (d) Addis Ababa (Ethiopia)
Answer: (d) Addis Ababa (Ethiopia)
Explanation
Time zones — which city is out of step?
| City | Country | Standard time |
|---|---|---|
| London | UK | UTC + 0 (GMT) |
| Lisbon | Portugal | UTC + 0 |
| Accra | Ghana | UTC + 0 |
| Addis Ababa | Ethiopia | UTC + 3 (East Africa Time) |
London, Lisbon and Accra are all close to the 0° (Greenwich) meridian.
Addis Ababa is at about 38.7° E — so it is 3 hours ahead.
Note: London and Lisbon move to UTC+1 in summer, but they move together and still differ from Addis Ababa.
Answer: (d) Addis Ababa (Ethiopia).
Why each option is right or wrong
- (a) Incorrect. London follows GMT (UTC+0) — same as Lisbon and Accra.
- (b) Incorrect. Lisbon uses Western European Time (UTC+0).
- (c) Incorrect. Accra uses GMT (UTC+0) all year — Ghana sits almost on the Greenwich meridian.
- (d) CORRECT. Addis Ababa is UTC+3 — ahead of the other three cities.
Key point
London, Lisbon, Accra = UTC+0. Addis Ababa = UTC+3 (East Africa Time).
Remember
Addis Ababa is 3 hours ahead of London, Lisbon and Accra.
Common mistakes
- Thinking Lisbon follows Central European Time like Madrid — Portugal uses UTC+0.
- Forgetting that Accra lies almost on the Prime Meridian.
- Getting confused by summer time — it does not change the answer here.
Exam tip
15° longitude = 1 hour. Addis Ababa at ~39° E ≈ 2.6 hours → rounded to UTC+3.
Sources
- NCERT Class VI — Globe: Latitudes and Longitudes
- NCERT Class XI — Fundamentals of Physical Geography
- IANA Time Zone Database