OK, this is what I have so far and I need to figure out the standard deviation and what I got doesn't really work, help me!! 
use strict;
my $number=0;  
my $line;  
my $score;  
my $std;  
my $avg;  
my $name;  
my $sum;
my $totd; 

open(IN, "pa5c.dat") || die ("Can't open file $!\n");
while($line = <IN>){
        chomp($line);
        ++$number;
        ($name, $score) = split(/:/, $line);
        $sum = $sum + $score;
        
        $totd += abs($sum - $avg);    
        $std = $totd / $number;
}

$avg = $sum / $number;
printf "The class average is:  %3.1f\n", $avg;
printf "The standard deviation is:  %3.1f\n", $std;

__END__#pa5.pl

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$totd is the total deviation. I'm supposed to get 5 for standard deviation but I get 261.3

In reply to Still confused by yabba

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