Play the note that sounds right. If the first string, fifth fret doesn't sound right, try the second string. If the second string doesn't sound right, try the third. Etc. I assume you can't read notation to check for a more accurate version.
I've run into a little problem attempting to nail a "Freebird" tab. On one string early on I run into one note only, and that's 5/. That's it. No 5/4 or 5/7, whatever. Question is: how do I play this note? Where am I sliding to?