Here is something using "mod". The function is pretty simple but the rounding requirements make it more complex. Comments on where I can improve this code and what practices I should stay away from are appreciated. 
use strict;

my $i;
my $roundup;
my $mod;
my $places;
my $modifier;

for $i (<DATA>) {
    chomp $i;
    $places = length $i;

    $modifier = 10;
    if ($places > 3) {
        $modifier = 100;
    }
    $mod = $i % $modifier;
    if ($mod) {
        $roundup = $i + ($modifier - $mod);
        print "$i rounded up is $roundup\n";
    }else{
        print "$i\n";
    }
}

__DATA__
0
2
9
11
20
21
112
1000
1325
1453
1999
10000
10001

[download]

In reply to Re: Rounding up nearest ten, hundred etc by terra incognita
in thread Rounding up nearest ten, hundred etc by nite_man

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