I searched the forums for fractions and found:

See either of these:

How can I create a fraction in Word that isn't in any of the fonts I have?
http://word.mvps.org/FAQs/Formatting/CreateFraction.htm

Create a fraction
http://www.gmayor.com/createfraction.htm


"Myrtle" wrote:

Word allows you to create fractions for fourths, thirds, and eights. I need
to be able to create fractions for sixteenths and thirty-seconds. Maybe
more. Word help guides you to the defaults (listed in the first sentence).