public IEnumerable <Tuple <ICustomer, decimal> > CreateCustomersAndCalcDiscounts() { var result = new List <Tuple <ICustomer, decimal> >(); decimal applePrice = 10; var veteran = _warVeteransFactory.Create(); var student = _studentsFactory.Create(); var veteranDiscount = _warVeteransFactory.AddDiscount(veteran, applePrice); var studentDiscount = _studentsFactory.AddDiscount(student, applePrice); result.Add(Tuple.Create(veteran, veteranDiscount)); result.Add(Tuple.Create(student, studentDiscount)); return(result); }