public void PriceTest(Tuple <string, string> city)
{
page.SetFlight(city.Item1, city.Item2);
page.ChooseTripType(); // set one way trips
page.ChooseDate(); // choose first available date
var t = page.GetPrice(1);
page.ChangePassengerNumber(2);
var t1 = page.GetPrice(2);
Assert.AreEqual(t, t1, 0.01);
}