In GoogleEarth, go to "tools" and then "options".
You can set the units to display as degrees and decimals of a degree OR degrees, minutes seconds and decimals of a second.
The default is degrees, minutes, seconds and decimals of a second.
The degrees, minutes, seconds prototcol is the same as time.
60 seconds to a minute and 60 minutes to a degree.
0.5 minutes is 30 seconds (half a minute) 0.5 degrees is 30 minutes (half an hour or degree)
If you copy 72.675 degrees from Google Earth, multiply 0.675 times 60 = 40.5 minutes
Your input would be W072d 40.5 minutes and would look like W072 40.5 for your Garmin.
You can also easily change your Garmin settings to any units you would like so as to maintain consistency with any mapping program from which you are obtaining coordinates.
Be extremely careful with your formats.
A misinterpretation of the units and faulty input will throw you off more than a country mile.
A minute of latitude is a nautical mile or 6,076 feet. Misinterpreting seconds for minutes can really do you in.
Scott
