"Object Does not Contain definition for Obtained" ASP.Net MVC

Question

I have created an object in a controller method which I am using in a view but it is giving me exception. Please tell me what I am doing wrong.

Here is my debugging result.

And here is my function to create the object.

public object GetResult(int CourseId, int Reg_Id, int RollNo, string name, string Description)
{
    var result = db.Results.Where(r => r.Course_Id == CourseId && r.Student_Reg_Id == Reg_Id && r.Description == Description).Single();
    var resultData = new {
          reg_Id = Reg_Id,
          Roll = 0,
          Name = "",
          Obtained = "",
          Total = ""
    };
    if (result != null)
    {
        resultData = new {
              reg_Id = Reg_Id,
              Roll = RollNo,
              Name = name,
              Obtained = result.Obtained_Marks.ToString(),
              Total = result.Total_marks.ToString()
        };
    }
    else
    {
        resultData = new {
            reg_Id = Reg_Id,
            Roll = RollNo,
            Name = name,
            Obtained = "Not Available",
            Total = "Not Available"
        };
    }
    return resultData;
}