Calculated Columns - Counif Functionality

Hi Team,

We have two tables like below

Problem

Problem Task

Problem has unique column Problem Id and Problem Task has PTASK ID as unique and we have feild Parent in PTASK ID which carries Problem ID.

Now I am looking to create a calculated column to list Number of Problem Tasks for a Problem ID.

Also From the Problem Task Table, there is a column named state which have multiple states like (Open / Assigned / Work In Progress / Pending / Closed)

I would like to could for the Problem ID how many Tasks are Closed.

For Eg: 

IF the Problem ID : PID1000 has 7 Tasks as below

Problem Task Table:

PTASK ID        State                                Parent

PTASK1001     Work in Progress              PID1000

PTASK1002     Assigned                           PID1000

PTASK1003     Closed                              PID1000

PTASK1004     Closed                             PID1000

.

.

PTASK1007   Closed                              PID1000

In Problem Table I want to count the number of PTASKS for a Problem and also the PTASKS Closed out of them,

To Count the PTASKS I have used the DAX as below in Problem Table

Problem Table on Calculated Column as below

Tot PTASKs = COUNTROWS(RELATEDTABLE(PTASK))

Another Column as 

But now i am not able see only blank information, 

I have created a One to Many Relation between Problem and Problem Task Table between Problem ID and Parent Field in PTASK Table.

Please advise how we can get the closed PTASKS Information

Appreciate your help.

Regards

Srini