How should I express fractions like 15/16ths in HTML?

Question

I know there are HTML entities for 1/2, 1/4, and 3/4, but are there others? Like 1/3 or 1/8? Is there a good way to encode arbitrary fractions?

Answer 1

Isn't just 15/16ths alright? Or even 15/16^ths (15/16ths)?