An important program was to be broadcast from Mumbai(73 east) at 7:30 pm. This was to be heard by some Indian sailor near Ivory Coast in West Africa at 20 degrees west longitude. What was the local time there?
Answers
Ivory Coast is located at 200W and Mumbai at 730E longitude. The difference in both the longitudes is 730+200=930 (Ivory Coast lies in the west of Prime Meridian and Mumbai to the east of the Prime Meridian, we will add the longitudes of both the places).
The difference in time between the two places is 930 X4= 372 (we multiply it by 4 because one degree of each longitude takes 4 minutes to travel to the other longitude).
372= 6 hrs and 12 minutes. Since Ivory Coast is to the west of Mumbai, its time is behind Mumbai. So we subtract the difference from the time in Mumbai.
7:30-6:12=1hr 18 min. Now we will subtract 1 hr and 18 minutes from 12:00am midnight.
12:00am-1hr and 18 minutes=10:42pm.
So, the local time in Ivory Coast will be 10:42pm