How can the multiplicative number (n) of a chemical series like polyethylene glycol (PEG) be a non-integer?

<https://en.m.wikipedia.org/wiki/PEG_400>


Down at chemical or molecular formula, it says:


C\_2n H\_4n+2 O\_n+1, like for all polyethylene glycols (PEG)s, but then says n=8.2 to 9.1....


Huh?


