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I am sorry, unfortunately you cannot perform calculations with dynamic fields, such as Configurable List or Infinite List widgets.
Depending on your requirements, you may be interested in using our Spreadsheet widget, which allows using calculation functions on its cells. However, this widget is not a dynamically expanding widget.
If you are interested about Form Calculations in general, I would advise you to take a quick look at our guide on How-to-perform-calculation-in-the-form
Please let us know if you need further help.