Here's a newbie approach w/o using  eval : ). 

sub s{
push @{$_[0]},0;
${$_[0]}[$#{$_[0]}] += ${$_[0]}[$_] for 0..$#{$_[0]}-1;
${$_[0]}[$#{$_[0]}] /= $#{$_[0]};
pop @{$_[0]};
}

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In reply to Re: "Junkyard" Puzzle: Average of Numbers (Newbie approach) by bambam
in thread "Junkyard" Puzzle: Average of Numbers by Masem

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