Originally posted by Zecc...

Just bumped against this code on my current project:

if($_REQUEST['discount_price'][$key] != 0) //avoid division by 0
{   
    $value = floatval($_REQUEST['list_price'][$key]);
    $discount = - 100 + ($value * 100) / $value;       
    $discount = round($discount, 2);
}
else
    $discount = 100;

With discounts like these, I think I'll stick to the list price, thank you.

Hint: $_REQUEST can be used to access GET/POST variables and cookies.
Hint 2: Figure out what "-100 + (x * 100) / x" works out to.