A town is located at longitude 45^\circ\text{E}. If the Greenwich Mean Time (GMT) is 8:00 … — JAMB UTME

A town is located at longitude $45^\circ\text{E}$ . If the Greenwich Mean Time (GMT) is 8:00 a.m., what is the local time in the town?

The local time in the town is 11:00 a.m.

Earth rotates from west to east, meaning places to the east experience solar noon earlier than places to the west. For every

15^\circ

of longitude moving eastward, time increases by 1 hour. Since the town is at

45^\circ\text{E}

, it is

45^\circ / 15^\circ = 3

hours ahead of Greenwich Mean Time (8:00 a.m.), making the local time 11:00 a.m.

Calculate the longitudinal difference between Greenwich Meridian (

0^\circ

) and the town (

45^\circ\text{E}

Longitudinal difference =

45^\circ - 0^\circ = 45^\circ

The longitudinal difference determines the total angular distance between the two locations.

Convert the longitudinal difference into time using the rate of

15^\circ = 1\text{ hour}

(or

1^\circ = 4\text{ minutes}

Time difference =

45^\circ \times 4\text{ minutes} = 180\text{ minutes} = 3\text{ hours}

Earth rotates

360^\circ

in 24 hours, which corresponds to

15^\circ

per hour.

Apply the rule 'East gain, West lose' relative to Greenwich Mean Time.

8:00 a.m. + 3 hours = 11:00 a.m.

Since the destination is east of the Greenwich Meridian, local time is ahead of GMT.

Longitude and Local Time Calculation

Question