A musical concert is scheduled to start in Los Angeles in U. S.A longitude 120° west on Saturday by 4pm. At what time and day should Nigerians switch on their t. V. Sets to watch the concerts live. Longitude of Nigeria 15° east

1 am on Sunday

Explanation:

Every distance of 15° longitude is an hour in time. This means that places that are 15° longitude apart have a time zone difference of an hour, areas that are 30° have a time zone difference of two hours and so on.

The time difference between a location in the U.S.A at longitude 120° west and Nigeria at 15° east would be:

= (120 + 15) / 15

= 9 hours

The 15 was added because Nigeria is east of the Greenwich meridian and the U.S. is west. The lines of longitude count down from the West to the East and get to zero at the Meridian. Then start again as they go east.

Areas east are also further in time than areas west so Nigeria is ahead of the U.S.

Nigeria is therefore ahead of that area by 9 hours. They would be able to watch the show at:

= 4pm + 9 hours

= 1 am on Sunday