XElement order =
new XElement("order",
new XElement("quantity", 10),
new XElement("price", 50),
	new XAttribute("idProduct", "P01"));

Decimal orderTotalAmount =
(Decimal)order.Element("quantity") *
(Decimal)order.Element("price");
Console.WriteLine("Celkov velikost objednvky: {0}", orderTotalAmount);
