Instead, it print out only the last column:

so I change to this line by adding the "." to join the 6 columns together and I get weird output like this:

You're not actually using the index variable ($index1). And you also need to properly re-initialize $variable1.

Would this do what you want?

my @ratio = map { sprintf '%.4f', $numerator[$_]/$denominator[$_] } 3.
+.8;
my $variable1 = join "\t", @ratio;
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