Good question! See Bitwise String Operators, which says "You may explicitly show which type of operation you intend by using "" or 0+". So this:

use strict;
use warnings;

my $a = '94';
my $b = '98';
my $c = 0+$a ^ 0+$b;
print "$c\n";

my $x = 94;
my $y = 98;
my $z = 0+$a ^ 0+$b;
print "$z\n";

my $i = 94 ^ 98;
print "$i\n";
[download]

Gives:

60
60
60
[download]