diff --git a/AspnetRunBasics/Entities/Cart.cs b/AspnetRunBasics/Entities/Cart.cs
index 0feee9c..4692ec9 100644
--- a/AspnetRunBasics/Entities/Cart.cs
+++ b/AspnetRunBasics/Entities/Cart.cs
@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using System.Linq;
 
 namespace AspnetRunBasics.Entities
 {
@@ -12,13 +13,7 @@ public decimal TotalPrice
         {
             get
             {
-                decimal totalprice = 0;
-                foreach (var item in Items)
-                {
-                    totalprice += item.Price * item.Quantity;
-                }
-
-                return totalprice;
+                return Items.Sum(item => item.Price * item.Quantity);
             }
         }
     }
diff --git a/AspnetRunBasics/Pages/Cart.cshtml.cs b/AspnetRunBasics/Pages/Cart.cshtml.cs
index 6a5600d..af5e050 100644
--- a/AspnetRunBasics/Pages/Cart.cshtml.cs
+++ b/AspnetRunBasics/Pages/Cart.cshtml.cs
@@ -2,6 +2,7 @@
 using System.Threading.Tasks;
 using AspnetRunBasics.Entities;
 using AspnetRunBasics.Repositories;
+using AspnetRunBasics.Repositories.Interfaces;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.RazorPages;
 
diff --git a/AspnetRunBasics/Pages/CheckOut.cshtml.cs b/AspnetRunBasics/Pages/CheckOut.cshtml.cs
index 80ca12e..c05e2bf 100644
--- a/AspnetRunBasics/Pages/CheckOut.cshtml.cs
+++ b/AspnetRunBasics/Pages/CheckOut.cshtml.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Threading.Tasks;
 using AspnetRunBasics.Repositories;
+using AspnetRunBasics.Repositories.Interfaces;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.RazorPages;
 
diff --git a/AspnetRunBasics/Pages/Index.cshtml.cs b/AspnetRunBasics/Pages/Index.cshtml.cs
index 92aa36c..adaad8d 100644
--- a/AspnetRunBasics/Pages/Index.cshtml.cs
+++ b/AspnetRunBasics/Pages/Index.cshtml.cs
@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using AspnetRunBasics.Repositories;
+using AspnetRunBasics.Repositories.Interfaces;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.RazorPages;
 
diff --git a/AspnetRunBasics/Pages/Order.cshtml.cs b/AspnetRunBasics/Pages/Order.cshtml.cs
index 20d6a4c..da0ad45 100644
--- a/AspnetRunBasics/Pages/Order.cshtml.cs
+++ b/AspnetRunBasics/Pages/Order.cshtml.cs
@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using AspnetRunBasics.Repositories;
+using AspnetRunBasics.Repositories.Interfaces;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.RazorPages;
 
diff --git a/AspnetRunBasics/Pages/Product.cshtml.cs b/AspnetRunBasics/Pages/Product.cshtml.cs
index c7a3e94..a3dd60d 100644
--- a/AspnetRunBasics/Pages/Product.cshtml.cs
+++ b/AspnetRunBasics/Pages/Product.cshtml.cs
@@ -3,6 +3,7 @@
 using System.Linq;
 using System.Threading.Tasks;
 using AspnetRunBasics.Repositories;
+using AspnetRunBasics.Repositories.Interfaces;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.RazorPages;
 
diff --git a/AspnetRunBasics/Pages/ProductDetail.cshtml.cs b/AspnetRunBasics/Pages/ProductDetail.cshtml.cs
index ceb4818..5753c2d 100644
--- a/AspnetRunBasics/Pages/ProductDetail.cshtml.cs
+++ b/AspnetRunBasics/Pages/ProductDetail.cshtml.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Threading.Tasks;
 using AspnetRunBasics.Repositories;
+using AspnetRunBasics.Repositories.Interfaces;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.RazorPages;
 
diff --git a/AspnetRunBasics/Repositories/CartRepository.cs b/AspnetRunBasics/Repositories/CartRepository.cs
index b5ea572..59e1736 100644
--- a/AspnetRunBasics/Repositories/CartRepository.cs
+++ b/AspnetRunBasics/Repositories/CartRepository.cs
@@ -4,6 +4,7 @@
 using System;
 using System.Linq;
 using System.Threading.Tasks;
+using AspnetRunBasics.Repositories.Interfaces;
 
 namespace AspnetRunBasics.Repositories
 {
diff --git a/AspnetRunBasics/Repositories/ContactRepository.cs b/AspnetRunBasics/Repositories/ContactRepository.cs
index 2609751..fe7c41c 100644
--- a/AspnetRunBasics/Repositories/ContactRepository.cs
+++ b/AspnetRunBasics/Repositories/ContactRepository.cs
@@ -2,6 +2,7 @@
 using AspnetRunBasics.Entities;
 using System;
 using System.Threading.Tasks;
+using AspnetRunBasics.Repositories.Interfaces;
 
 namespace AspnetRunBasics.Repositories
 {
diff --git a/AspnetRunBasics/Repositories/Interfaces/ICartRepository.cs b/AspnetRunBasics/Repositories/Interfaces/ICartRepository.cs
index a4e2070..0bffec6 100644
--- a/AspnetRunBasics/Repositories/Interfaces/ICartRepository.cs
+++ b/AspnetRunBasics/Repositories/Interfaces/ICartRepository.cs
@@ -1,7 +1,7 @@
-using AspnetRunBasics.Entities;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
+using AspnetRunBasics.Entities;
 
-namespace AspnetRunBasics.Repositories
+namespace AspnetRunBasics.Repositories.Interfaces
 {
     public interface ICartRepository
     {
diff --git a/AspnetRunBasics/Repositories/Interfaces/IContactRepository.cs b/AspnetRunBasics/Repositories/Interfaces/IContactRepository.cs
index 2ec05cf..ca78444 100644
--- a/AspnetRunBasics/Repositories/Interfaces/IContactRepository.cs
+++ b/AspnetRunBasics/Repositories/Interfaces/IContactRepository.cs
@@ -1,7 +1,7 @@
-using AspnetRunBasics.Entities;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
+using AspnetRunBasics.Entities;
 
-namespace AspnetRunBasics.Repositories
+namespace AspnetRunBasics.Repositories.Interfaces
 {
     public interface IContactRepository
     {
diff --git a/AspnetRunBasics/Repositories/Interfaces/IOrderRepository.cs b/AspnetRunBasics/Repositories/Interfaces/IOrderRepository.cs
index 4371a22..fe445b0 100644
--- a/AspnetRunBasics/Repositories/Interfaces/IOrderRepository.cs
+++ b/AspnetRunBasics/Repositories/Interfaces/IOrderRepository.cs
@@ -1,8 +1,8 @@
-using AspnetRunBasics.Entities;
-using System.Collections.Generic;
+using System.Collections.Generic;
 using System.Threading.Tasks;
+using AspnetRunBasics.Entities;
 
-namespace AspnetRunBasics.Repositories
+namespace AspnetRunBasics.Repositories.Interfaces
 {
     public interface IOrderRepository
     {
diff --git a/AspnetRunBasics/Repositories/Interfaces/IProductRepository.cs b/AspnetRunBasics/Repositories/Interfaces/IProductRepository.cs
index aed62df..65b5984 100644
--- a/AspnetRunBasics/Repositories/Interfaces/IProductRepository.cs
+++ b/AspnetRunBasics/Repositories/Interfaces/IProductRepository.cs
@@ -1,8 +1,8 @@
-using AspnetRunBasics.Entities;
-using System.Collections.Generic;
+using System.Collections.Generic;
 using System.Threading.Tasks;
+using AspnetRunBasics.Entities;
 
-namespace AspnetRunBasics.Repositories
+namespace AspnetRunBasics.Repositories.Interfaces
 {
     public interface IProductRepository
     {
diff --git a/AspnetRunBasics/Repositories/OrderRepository.cs b/AspnetRunBasics/Repositories/OrderRepository.cs
index a6d4a4d..d442c16 100644
--- a/AspnetRunBasics/Repositories/OrderRepository.cs
+++ b/AspnetRunBasics/Repositories/OrderRepository.cs
@@ -5,6 +5,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
+using AspnetRunBasics.Repositories.Interfaces;
 
 namespace AspnetRunBasics.Repositories
 {
diff --git a/AspnetRunBasics/Repositories/ProductRepository.cs b/AspnetRunBasics/Repositories/ProductRepository.cs
index 15c6675..38d793f 100644
--- a/AspnetRunBasics/Repositories/ProductRepository.cs
+++ b/AspnetRunBasics/Repositories/ProductRepository.cs
@@ -4,6 +4,7 @@
 using System.Threading.Tasks;
 using AspnetRunBasics.Data;
 using AspnetRunBasics.Entities;
+using AspnetRunBasics.Repositories.Interfaces;
 using Microsoft.EntityFrameworkCore;
 
 namespace AspnetRunBasics.Repositories
diff --git a/AspnetRunBasics/Startup.cs b/AspnetRunBasics/Startup.cs
index bdf67b6..95a335b 100644
--- a/AspnetRunBasics/Startup.cs
+++ b/AspnetRunBasics/Startup.cs
@@ -1,5 +1,6 @@
 using AspnetRunBasics.Data;
 using AspnetRunBasics.Repositories;
+using AspnetRunBasics.Repositories.Interfaces;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.EntityFrameworkCore;