WAEC Geography 2011 Papers

Concept:Time changes by 1 hour for every $15^\circ$ of longitude. A place to the west is behind in time.Explanation:Town X is on longitude $15^\circ\mathrm{E}$, and town Y is on longitude $75^\circ\mathrm{W}$.Since the towns are on opposite sides of the Prime Meridian, add the longitudes to find the total difference.Total longitude difference $= 15^\circ + 75^\circ = 90^\circ$.Now convert the longitude difference into time difference.$90^\circ \div 15^\circ = 6$ hours.So, there is a time difference of 6 hours between town X and town Y.Town Y is west of town X, so its local time is earlier.Time at Y $= 1.00\,\mathrm{pm} - 6$ hours $= 7.00\,\mathrm{am}$.Since subtracting 6 hours from 1.00 pm stays within the same day, the day remains Saturday.Answer:7.00 am on Saturday.