use Spreadsheet::WriteExcel;
#Question One
my $workbook  = Spreadsheet::WriteExcel->new('Q01.xls');
my $worksheet = $workbook->addworksheet();
$worksheet->write('A1', '=Results.xls!D4' );

$preformula = "3";
$increment = "13";
for($i=1; $i<=90; $i++){
$precell=$i + "1";
$cell = "B".$precell;
$formula = "=Results.xls!E".$preformula;
$worksheet->write($cell, $formula );  
$preformula = $preformula + $increment;
}