Thank you for your help. However this is not exactly what I was looking for.
This gives me the number of compatibles EACH user has, I would like to know the AVERAGE compatibles that I have per user given all the users.
So in essence it should take all the number that result from the query that you produced, sum them up and divide by the number of rows returns.
It should be a 1 number answer like 15.45 or 7.89.
is there a way to achieve it ?