Selecting Random Cells in a Table

Hello!

I am trying to set up this activity so that there are three tables (5 rows and 10 columns), each with a Random Sample button.
On slide 4 I want the button to select 10 random cells and place an “x” in them.
On slide 6 I want the button to select two random cells from each row and place an “x” in them.
On slide 8 I want the button to select two random cells from each column and place an “x” in them.

I’ve been looking at random number generators without repeats (Generating random integers (without repeats)) and get lost in the graph equations.

Can anyone help me out with this?
Here is the activity: