Ok, here's my rediculous approach that will give the exact answer... Thanks to tilly for the 'gcd' function, that was great! :-D

use strict;
use warnings;

while (<DATA>) {
    chomp;

    my $a = $_;
    $a =~ s/^\d?\.0*?//;     # strip 0.0 part from 0.035

    my $b = length($_) - 2;  # how many zero's we need
                             # assume in 0.0x form
    my $c = 10 ** $b;

    my $gcd = gcd($a, $c);
    $a /= $gcd;
    $c /= $gcd;

    print $_, "\t", "$a/$c", "\n";
}

# ---- borrowed from tilly's code ----
sub gcd {
  my ($n, $m) = @_;
  while ($m) {
    my $k = $n % $m;
    ($n, $m) = ($m, $k);
  }
  return $n;
}

__DATA__
0.035
0.037
0.039
0.041
0.043
0.046
0.048
0.058
0.068
0.078
0.35
0.37
0.39
0.41
0.43
0.46
0.48
0.58
0.68
0.78

[download]

And the output -
0.035   7/200
0.037   37/1000
0.039   39/1000
0.041   41/1000
0.043   43/1000
0.046   23/500
0.048   6/125
0.058   29/500
0.068   17/250
0.078   39/500
0.35    7/20
0.37    37/100
0.39    39/100
0.41    41/100
0.43    43/100
0.46    23/50
0.48    12/25
0.58    29/50
0.68    17/25
0.78    39/50

[download]

In reply to Re: Percentages to Fractions (The good, the bad and the **rediculous**) by Roger
in thread Percentages to Fractions by David Caughell

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