How do I enter a latitude longitude into my GPS using Google Earth coordinates?

I know how to enter the coordinates, but the problem I'm having is that Google Earth gives me 2 digits at the end but my GPS wants 3.

For example (random coordinate):

Google Earth:

40掳26'47"N

79掳58'36"W

Where the 47 and 36 are, which are both double digits, my GPS is asking me for 3 digits. Should I add a "0" before or after them on my GPS?How do I enter a latitude longitude into my GPS using Google Earth coordinates?
It probably doesn't matter a lot. The difference would likely be a matter of a few feet. But, so you'll know--



first, the 40掳26'47'' reading is in degrees, minutes, and seconds of arc...if the 47'' increases , it goes up to 59, then 'rolls over' like an odometer in a car and the 26 becomes 27, and the 59 becomes 00.



Chances are the GPS wants degrees, minutes and thousands of a minute, not minutes and seconds. So, to be precise, take the 47'' for example, and convert it to thousands of a minute...47 divide 60 is .783, so the entered number would be 40掳 26.783'' .



The difference between 40掳 26.783'' and 40掳 26.470 would be 0.313...(this is wrong, of course...I'm just saying if you entered 470 for your 3 digits that the GPS wants..."lying'' to it, so to speak)...and 0.313 seconds of arc would be about 30 feet error at 45掳 N or S latitude, since at that latitude 45掳 is about 49 miles.