A topographic quadrangle is a 30' series map (it covers 30' longitude and latitude). If the western longitude boundary is 120 degrees 02 feet 30 inches, what is the longitude of the eastern boundary?

Answer 1

That depends upon which hemisphere the map depicts -- Eastern or Western?

Answer 2

It doesn't specify. Can you tell me the answer to both?

Answer 3

Don't you mean, 120 degrees, 2 minutes, 30 seconds?

http://en.wikipedia.org/wiki/Latitude

In the Western Hemisphere, the longitude numbers get larger as you go west. So 120 degrees, 02 minutes, 30 seconds minus 30 degrees equals 90 degrees, 02' 30".

In the Eastern Hemisphere add 30 degrees to the boundary longitude.

Answer 4

Thank you.