$ perl -e'
use List::Util q/sum/;
my %HoA = (
    A => [ 2.34, 4.12, 5.32 ],
    B => [ 1.42, 8.15 ],
    C => [ 8.42, 0.23, 0.45, 6.43 ],
    );
for my $key ( keys %HoA ) {
    printf "%s\t%.2f\n", $key, sum( @{ $HoA{ $key } } ) / @{ $HoA{ $ke
+y } };
    }
'
A       3.93
C       3.88
B       4.79
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