Is it possible to convert strings to math operators?

I didn't see anything in the gawk(1) manpage for doing this but it seems 
like it should be possible.

ex.  oz to lb using old-school units(1) command:
--
$ units -1 oz lb
    * 0.0625

# this works:
$ echo "16 $(units -1 oz lb)" |awk '{print $1 " oz = " $1 * $3 " lb"}'
16 oz = 1 lb

# this does NOT work:
$ echo "16 $(units -1 oz lb)" |awk '{print $1 " oz = " $1 $2 $3 " lb"}'
16 oz = 16*0.0625 lb

--

Is there a way to tell (g)awk to interpret strings like "*", "/", "+", 
"-", etc. as actual math operators?