If you want a string, for output, you can use `num` (http://files.arcfn.com/doc/string.html#num):
arc> (num (/ 3 2)) "1.5"
arc> (nearest (/ 3 2) .1) 1.5
arc> (type (nearest (/ 3 2) .1)) num
So I can use this:
(coerce (num (/ 3 2)) 'num) --> 1.5
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