If you want to keep the pairings for future manipulation then you might like:

use strict;
use warnings;

my @pairs = map {[$_]} split  ' ', 'A G C T G G G G A C T T T A G C';
my @nums = split ' ', '34 23 43 45 34 43 45 7 45 43 12 34 32 56 43 67'
+;

push @{$pairs[$_]}, $nums[$_] for 0 .. $#pairs;

print "$_->[0]: $_->[1], " for grep $_->[1] >= 10, @pairs;
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Prints:

A: 34, G: 23, C: 43, T: 45, G: 34, G: 43, G: 45, A: 45, C: 43, T: 12, 
+T: 34, T: 32, A: 56, G: 43, C: 67,
[download]