Add Category Value

[billjohnson]

I am customizing sample app
Inventory Management App v2.000041
On the menu there is “Inventory Values” view
This takes me to a slice named “prices and values” that gives the $ amount of available stock for each product (unit price multiplied by quantity available).I want to keep this as it is and add a sum of categories as well.
i.e. total value of all products in “groceries” category.
I’m very new to Appsheet… so please detail as much as possible.