How to create a dynamic top N for a matrix with multiple values

Hi donnie17 
Yes, you can achieve it.
As a first step create a parameters table for selecting Top n 

And the 2 measures according to yours, like in my case:

1.

TopN country profits =

VAR SelectedTop = SELECTEDVALUE('Top n'[Top n])

RETURN

SWITCH(TRUE(),

    SelectedTop = 0, [total profits (K/$)],

    RANKX (

            ALLSELECTED(  'Customers'[Country] ),

            [Total sales (K/$)]

                )

                  <= SelectedTop,

        [total profits (K/$)]

)

2. 

TopN country sales =

VAR SelectedTop = SELECTEDVALUE('Top n'[Top n])

RETURN

SWITCH(TRUE(),

    SelectedTop = 0, [total_sales],

    RANKX (

            ALLSELECTED(  'Customers'[Country] ),

            [Total sales (K/$)]

                )

                  <= SelectedTop,

        [Total sales (K/$)]

)

Result :

The pbix is attached

If this post helps, then please consider Accepting it as the solution to help the other members find it more quickly

Hi donnie17  You already done all the work. You just need to do a small thing.  Select the matrix visual, go to filter pane, Select Total Sales and set to "Is not blank", Click apply. You are done.

I have tried to implement your scenario. See images:

No filter applied:

After applied filter:

Hope this helps!!

If this solved your problem, please accept it as a solution!!

Best Regards,
Shahariar Hafiz