- $discount = $form->round_amount($form->{"sellprice_$i"} * $form->{"discount_$i"} / 100, $decimalplaces);
- $linetotal = $form->round_amount(($form->{"sellprice_$i"} - $discount) / $price_factor, $decimalplaces);
- $linetotal = $form->round_amount($linetotal * $form->{"qty_$i"}, 2);
+ $discount = $form->round_amount($form->{"qty_$i"} * $form->{"sellprice_$i"} * $form->{"discount_$i"} / 100 / $price_factor, 2);
+ $linetotal = $form->round_amount($form->{"qty_$i"} * $form->{"sellprice_$i"} * (100 - $form->{"discount_$i"}) / 100 / $price_factor, 2);