$ perldoc -q decimal 
Found in /opt/perl/lib/5.8.1/pod/perlfaq4.pod
       Why am I getting long decimals (eg, 19.9499999999999)
       instead of the numbers I should be getting (eg, 19.95)?

               Internally, your computer represents floating-
               point numbers in binary. Digital (as in powers of
               two) computers cannot store all numbers exactly.
               Some real numbers lose precision in the process.
               This is a problem with how computers store numbers
               and affects all computer languages, not just Perl.

               perlnumber show the gory details of number repre-
               sentations and conversions.

               To limit the number of decimal places in your num-
               bers, you can use the printf or sprintf function.
               See the "Floating Point Arithmetic" for more
               details.

                       printf "%.2f", 10/3;

                       my $number = sprintf "%.2f", 10/3;
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