Official Answer Key & Detailed Solution
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Correct Answer: Option (B) — 7°30’ W .
Concept & Option Breakdown
Standard Reference Verified• Indian Standard Time (IST) is based on 82°30' E. • Time at IST = 12:00 PM (noon); time at target place = 6:00 AM (6 hours behind). • Since the place is behind in time, it lies to the west. • 1 hour = 15° of longitude, so 6 hours = 6 × 15° = 90° difference. • Target longitude = 82°30' E - 90° = 7°30' W.
Earlier time means west. Subtract 90° from 82.5° E to get 7.5° W (7°30' W).
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