Assuming the leading whitespace is a typo and you are extracting the line correctly, all you need to do is compute and print the average. There are many ways to do this - here is just one:

#!/usr/bin/env perl 
use strict;
use warnings;
use Statistics::Lite 'mean';

my $line = 'Charles 25 24 26';

my ($name, @fields) = split (/ /, $line);
my $mean = mean (@fields);
printf "%s average is %.2f\n", $name, $mean;
[download]