public void Execute() { var selfCheckout = new SelfCheckout(); foreach (var index in Enumerable.Range(1, 3)) { selfCheckout = EnterItem(selfCheckout, index); } var formattedSelfCheckout = new FormattedSelfCheckout(selfCheckout); Console.WriteLine("Subtotal: {0}", formattedSelfCheckout.SubTotal()); Console.WriteLine("Tax: {0}", formattedSelfCheckout.Tax()); Console.WriteLine("Total: {0}", formattedSelfCheckout.Total()); }