In the spirit of TMTOWTDI:

use strict;
use warnings;

my  %hash_name = (a => 1, b => 2, c => 3);
my ($max_key, $max_value) = each %hash_name;

while  (my ($key, $value) = each %hash_name)
{
    if ($value > $max_value)
    {
        $max_key   = $key;
        $max_value = $value;
    }
}

printf "Max value is %d, which corresponds to key %s\n", $max_value, $
+max_key;
[download]

Output:

 1:13 >perl 1994_SoPW.pl
Max value is 3, which corresponds to key c

 1:18 >
[download]

See each.

Hope that helps,