URGENT :Calculating Duration of an SCTASK & RITM.

[Mounika B1]

I  want to calculate "duration" for task & RITM"
For incident, we can calculate "duration", but I can't calculate it for task.
If the item is Open:
Display the time elapsed from the request submission date to the current date.
If the item is Closed:
Display the time between the opened date and the closed date.

[Mark Manders]

Why can't you calculate that? It works in the same way. How are you calculating? Are you using OOB metrics, PA, custom code? 

When you say something is 'urgent' you need to provide enough information that we can help you. Especially because you don't even mention why you can do something on one record that you can't do on another, while those records have the exact same fields.