Help Me please.

13 degrees  17 minutes 50 seconds

We don't need to worry about the degree conversion..we need to convert the minutes and seconds to decimal degrees

There are 60 minutes to each degree  so we can express this as     17/60  degrees

And there  are  3600 seconds in each degree so we can express this as  50/3600 degrees 

So...adding   D, M ,S  in terms of degrees, we have...

D   +  M     +   S     =

13°  + 17/60° + 50/3600°   =

13.297222°  =   13.297°  (rounded)

BTW, Manuel....here's an app where you can check these conversions :

https://www.rapidtables.com/convert/number/degrees-minutes-seconds-to-degrees.html

However....if you use this fractional adding procedure above.....you shouldn't have much trouble on these!!!

Thank You!!!, Cphill