public void LatteClass_CostMethod_ShouldReturnCorrectPriceBasedOnCoffeSize(CoffeSizeType coffeeSize) { // Arrange var basePrice = 3.00m; var expectedCost = basePrice + (((int)coffeeSize / 100) * basePrice); // Act var obj = new Latte(coffeeSize); // Assert Assert.That(obj.Cost(), Is.EqualTo(expectedCost)); }