Perth located on 118th East Longitude will be celebrating New Year event on 1st of January 2017 at 6:00 AM . At that time, what would be time at Los Angeles located on 1100 West Longitude?

To find the time in Los Angeles (110 W) relative to Perth (118 E), we first calculate the total longitudinal difference. Since they are in different hemispheres, the difference is 118 + 110 = 228 . The Earth rotates 360 in 24 hours, meaning 15 equals 1 hour and 1 equals 4 minutes . Dividing 228 by 15 gives a time difference of 15 hours and 12 minutes . Because Los Angeles is west of Perth, it is behind in time . Subtracting 15 hours and 12 minutes from 6:00 AM on 1st January 2017 involves moving backward through midnight. Subtracting 6 hours reaches 12:00 AM (midnight) of 1st January. Subtracting the remaining 9 hours and 12 minutes from midnight leads to 2:48 PM on the previous day, 31st December 2016 . This confirms Los Angeles is 15 hours and 12 minutes behind Perth's local time.

Sources

1. [1] Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 2: The Earth's Crust > Longitude and Time > p. 11