The one liners above are fine, but if I needed to incorporate this into a larger script, I would write the filtered data to a new file, then replace the original with the new file. 

use strict;
use IO::File;

#open the original report for reading
my $file = IO::File->new("data.txt","r") or die($!);
#Create a new file to write to 
my $filtered_file = IO::File->new("data_filtered.txt","w") or die($!);
#read report file
while ( my $line = <$file> ) {
    #remove newline
    chomp($line);
    my ( $data, $number ) = split ",", $line;
    $filtered_file->print("$line\n") if $number < 47;
}
$file->close;
$filtered_file->close;
# Replace the original file
rename("data_filtered.txt","data.txt");

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In reply to Re: Removing lines ending with integers larger than x by thunders
in thread Removing lines ending with integers larger than x by dtbach

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