Precision??

I'm confused with how the precision works in RPG right now?  I'm creating 
a program to convert Miles Per Gallon, to Litres Per 100 Km, for my own 
personal use.  Anyway, I can code the calculation two different ways, one 
truncates the other does not.  Using the temp field in each step works 
great, exactly what I want, but if I try to do it all in one calculation I 
get truncation.  What gives?  Here's the definitions and code.

     ?*-Define constant 
fields--------------------------------------------------------
     d Conv_To_Km      c                   Const(0.621371192237334)
     d Conv_To_Litres  c                   Const(3.78623545651745)
     ?*-Define stand alone 
fields-----------------------------------------------------
     D Temp            S             15  5 
     D Ltrkm           S             10  2       
...
     ?* Calc the litres per 100 km based off the mpg
     c                   Eval      Temp = Mpg / Conv_To_Litres
     c                   Eval      Temp = Temp / Conv_To_Km
     c                   Eval      Ltrkm = 100 / Temp
This works great, but next line (which is pretty much the whole thing in 
one) is giving me fits.
     c                   Eval      Temp = 
100/((Mpg/Conv_To_Litres)/Conv_To_Km)
RNF7551: Result of numeric operation is truncated to 0 decimal places.  



Ron Power
Programmer
Information Services
City Of St. John's, NL
P.O. Box 908
St. John's, NL
A1C 5M2
Tel: 709-576-8132
Email: rpower@xxxxxxxxxx
Website: http://www.stjohns.ca/
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