my %hash;
my @topkeys = qw/a b c/;
my @innerkeys = qw/1 2/;
my @values = qw/5.5 3.2 15.0 -22 .02 .15/;

for my $k ( @topkeys ) {
    for my $i ( @innerkeys ) {
        $hash{$k}{$i} = shift @values;
    }
}

print join "\t", (map { sprintf("%.1f",$hash{$_}{1}) } qw/a b c/), "\n";

# or, if "map" is too tough for the inexperienced:

printf( "%.1f\t", $hash{$_}{1} ) for ( qw/a b c/ );
print "\n";