public void TestAddition()
{
Duration original = new Duration(5, 1000.0);
Duration add = Duration.FromSeconds(50.0);
Duration result = original + add;
Assert.AreEqual(5, result.Days);
Assert.AreEqual(1050.0, result.Seconds);
original = new Duration(5, 8382.1);
add = new Duration(1, 10.0);
result = original + add;
Assert.AreEqual(6, result.Days);
Assert.AreEqual(8392.1, result.Seconds);
original = new Duration(5, 86000.0);
add = Duration.FromSeconds(1000.0);
result = original + add;
Assert.AreEqual(6, result.Days);
Assert.AreEqual(600.0, result.Seconds);
}