So far as I know, only Red Hat's exams use the term,
"floating range," in reference to LVM. I see no mention of it, for example, in the relevant man-pages.
In an obligatory Google search, I see only many-more questions like the one that you asked.
And, to be perfectly frank,
I have no idea what Red Hat's examiners are talking about, and I find no clues in the "solution" offered in post #1.
The fundamental operations that must take place are to resize the file-system and to alter the amount of physical storage allocated to the logical volume. The only, but extremely important(!), "trick" is that, if resizing
downwards, you must shrink the filesystem
first so that it won't have put anything in an area of storage that's about to disappear forever. (But, then again, who-the-hell resizes
downwards, anyway?)
What Red Hat means by "floating range," I have no cucking floo.