Can't Fetch Metadata from breeze ,error occurred - breeze

Question

I am trying to develop some sort of calculator using breeze so that while calculating if user wanna save the datails he/she can save it into database and can display using breeze webapi.
My page with knockout bindings to get data from breeze
<div id="calculatorList">
<table class="table table-striped">
<tbody data-bind="foreach: calculate">
<tr>
<td data-bind="text: FirstNumber"></td>
<td data-bind="text: Operator"></td>
<td data-bind="text: SecondNumber"></td>
<td data-bind="text: Output"></td>
<td>
<button data-bind="click: editCalculate" class="btn btn-primary">Edit</button>
</td>
<td>
<button data-bind="click:deleteCalculate" class="btn btn-primary">Delete</button>
</td>
</tr>
</tbody>
</table>
</div>
My DbContext cs file
public class ResultDbContext : DbContext
{
public ResultDbContext() : base("DefaultConnection")
{
Database.SetInitializer<ResultDbContext>(null);
}
public DbSet<Result> Results { get; set; }
}
Controller
[BreezeController]
public class CalculatorController : ApiController
{
readonly EFContextProvider<ResultDbContext> _cp = new EFContextProvider<ResultDbContext>();
[HttpGet]
public string Metadata()
{
return _cp.Metadata();
}
[HttpGet]
public IQueryable database()
{
return _cp.Context.Results;
}
[HttpPost]
public SaveResult SaveChanges(JObject saveBundle)
{
return _cp.SaveChanges(saveBundle);
}
}
But still I am getting this following error
{"$id":"1","$type":"System.Web.Http.HttpError, System.Web.Http","Message":"An error has occurred.","ExceptionMessage":"Method not found: 'System.Data.Objects.ObjectContext System.Data.Entity.Infrastructure.IObjectContextAdapter.get_ObjectContext()'.","ExceptionType":"System.MissingMethodException","StackTrace":" at Breeze.WebApi.EFContextProvider`1.GetMetadataFromDbContext(Object context)\r\n at Breeze.WebApi.EFContextProvider`1.GetMetadataFromContext(Object context)\r\n at Breeze.WebApi.EFContextProvider`1.BuildJsonMetadata()\r\n at Breeze.WebApi.ContextProvider.Metadata()\r\n at SpaCalculator.Controllers.CalculatorController.Metadata() in c:\\Users\\arajak\\Documents\\Visual Studio 2012\\Projects\\Calculator\\SpaCalculator\\Controllers\\CalculatorController.cs:line 22\r\n at lambda_method(Closure , Object , Object[] )\r\n at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.<>c__DisplayClass10.<GetExecutor>b__9(Object instance, Object[] methodParameters)\r\n at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.Execute(Object instance, Object[] arguments)\r\n at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ExecuteAsync(HttpControllerContext controllerContext, IDictionary`2 arguments, CancellationToken cancellationToken)\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Controllers.ApiControllerActionInvoker.<InvokeActionAsyncCore>d__0.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__0.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Controllers.ActionFilterResult.<ExecuteAsync>d__2.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Dispatcher.HttpControllerDispatcher.<SendAsync>d__1.MoveNext()"}
Can anyone will say why this error is occurring