$variable1 = '';
    print OUT1 "$first[0]\t$first[1]\t$first[2]\t";
    for my $index1 (3..8)
    {
      my $ratio1 = sprintf( "%.4f%s", $numerator/$denominator,"\t");
      #print OUT1 "$ratio1";
      $variable1 = "$ratio1"; # problem with this line  
    } 
   
    print OUT1 "$variable1";  # print to textfile
    print OUT1 "\n";


##</code><code>##

           A98  0.98  123  4  4  4  4  4   4
           A09  0.87  154  2  6  5  8  3   1
           A12  0.12  873  6  1  2  4  7   0  

##</code><code>##

            A98  0.98  123  4
            A09  0.87  154  1
            A12  0.12  873  0

##</code><code>##

            $variable1 .= "$ratio1"; # problem with this line  

##</code><code>##

      
            A98  0.98  123  4  4  4  4  4  4
            A98  0.98  123  4  4  4  4  4  4  2  6  
            A98  0.98  123  4  4  4  4  4  4  2  6  4 
            A98  0.98  123  4  4  4  4  4  4  2  6  4  6 
            A98  0.98  123  4  4  4  4  4  4  2  6  4  6  1 ...