Theory:

Geographic coordinate system (GCS) is a coordinate system, which defines two-dimensional coordinates based on the earth's actual surface, which is three-dimensional.
In GCS, latitudes and longitudes are used to represent the coordinates. Latitudes and longitudes, in general, are represented in degrees, minutes, seconds.
Where one degree is equal to \(60 minutes\) and is equal to \(3600 seconds\).
\(1° = 60' = 3600"\).
One minute is equal to \(1/60 degrees\).
\(1' = (1/60)° = 0.01666667°\).
One second is equal to \(1/3600 degrees\).
\(1" = (1/3600)° = 0.000277778°\).
 
Important!
The DMS format: DMS format refers to the symbols that are used to represent degrees, minutes, seconds.
  • Degrees are represented as \(d°\).
  • Minutes are represented as \(m'\).
  • Seconds are represented as \(s"\).
Conversion of latitude and longitude to its decimal form:
The decimal degrees DD is equal to:
 
\(DD =\) d°+m60+s3600
Example:
Convert \(45\) degrees \(20\) minutes and \(35\) seconds angle to decimal degrees
 
\(45\)° \(20\)' \(35\)".
 
The decimal degrees DD is equal to
\(DD =\) d°+m60+s3600 \(=\) 40°+2060+353600 \(= 40.34306°\)