Discount::calculateOriginalPrice

static function calculateOriginalPrice($price, $discountRate)
{
	$price = doubleval($price);
	$discountRate = doubleval($discountRate);
	if ($discountRate === 100.0)
	{
		return 0.0;
	}

	return (100 * $price) / (100 - $discountRate);
}