Hi valavanp, Try like this,

use strict;
use warnings;
my $str = "2A2B2C";
my %p = (A => 1.5, B => 2.5, C => 3.5);

my @arr = split/(?=\d+)/, $str;
my $range = 50;
map{s/^(\d+)([^\d]+)$/(($p{$2}."\*") x $1)."$range\/100"/e; $range+=5;
+}@arr;
$str = eval join'*', @arr;

print $str;
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Updated
valavanp, see below for The range is (50,55,60,65,70,75,80,85,90). How can i code that. your solutions.

use strict;
use warnings;
my $str = "2A2B2C";
my %p = (A => 1.5, B => 2.5, C => 3.5);

my @arr = split/(?=\d+)/, $str;
my @range = (50,55,60,65,70,75,80,85,90);
my $i =0;
map{s/^(\d+)([^\d]+)$/(($p{$2}."\*") x $1)."$range[$i]\/100"/e; $i++;}
+@arr;
$str = eval join'*', @arr;

print $str;
[download]