If G.M.T. or G.A.T. is less than L.M.T. or L.A.T. respectively, Lo. is East.
Example:
In longitude 81° 15' W, L.M.T. is April 15d 10h 17m 30s A.M. What is G.M.T.?
L.M.T. 15d 10h 17m 30s A.M.
- 12
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L.M.T. 14d 22h 17m 30s
5 25 W +
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G.M.T. 15d 3h 42m 30s
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G.M.T. April 15d 3h 42m 30s
L.M.T. April 15d 10h 17m 30s A.M.
In what Lo. is ship?
G.M.T. 15d 3h 42m 30s
L.M.T. 14d 22h 17m 30s
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Lo. in T 5h 25m 00s W
Lo. = 81° 15'W