Data collection between ages in mvc5

Question

hi guys I have tried to collect data between ages but there is an error I do not know why here is my code my controller

public ActionResult AllCuont()
{ var query = (from t in db.Pations
let range = ( t.Age >= 0 && t.Age < 10 ? "0-9" :
t.Age >= 11 && t.Age < 15 ? "10-14" :
t.Age >= 15 && t.Age < 50 ? "15-50" : "50+" )
group t by range into g
select new UserRange { AgeRange = g.Key, Count = g.Count() }).ToList(); //add the sum column.
query.Add(new UserRange() { AgeRange = "Sum", Count = query.Sum(c => c.Count) }); ViewBag.UserData = query;
return View(); }

and this is my model for To collect value

namespace Archive.Models
{
public class UserRange {
public string AgeRange { get; set; }
public IEnumerable<Pation> Count { get; set; } }
}

i Can't find the problem can you help me

the problem in my controller here