What is the time at Accra at longitude Oº when the local time at longitude 450W is 12 noon

Analyze the question: Accra lies on (approximately) longitude 0°, the Greenwich Meridian. We are told the local time at longitude 45°W is 12 noon, and we need the time at 0°.

Concept:

• The Earth rotates 360° in 24 hours, so 15° = 1 hour (1° = 4 minutes).
• Places to the east are ahead in time, and places to the west are behind.
• 0° is east of 45°W, so it is ahead of 45°W.

Solution:

1. Longitude difference = 45° − 0° = 45°
2. Time difference = 45° ÷ 15° = 3 hours
3. Since 0° is east of 45°W, its time is ahead: 12 noon + 3 hours = 3 p.m.

Answer: Accra's time is 3 p.m., which is option A.

Tip: Remember "East is Early (ahead), West is Wasted (behind)", or "Go east, add; go west, subtract." Always divide the longitude difference by 15 to get the hour difference.