Counter of button clicks.

Hi,

i'm preparing a test for the user where he have to do some actions ( usually its button clicks and text entry boxes). If he won't do it in right way there is a window with information what he should do and a button "Continue".  

For this button "Continue" there is execute advanced action:

1. Go to the next slide

2. Increment "Wrongs" by 1.

*"Wrongs" - variable set to 0 at the beggining. 

And there is a problem. I would like to have at the last slide something like this:

"Sorry u haven't pass the test. / Great u passed the test. You have scored: 30% (3 points)."

How can i count and add something like this? - "You have scored: 30% (3 points)."

Please help 🙂