Go round the table asking each person how many legs they have. The answer should, in most cases, be the standard two. (If it is otherwise, you will have started by saying that you will prove that most of your fellow diners have more than the average number of legs.)
You will then assert that, because there are some people with one leg or even no legs, the average number of legs per person is actually 1.99 recurring. It has already been demonstrated that everybody in the room has two legs, therefore each of them has more than the average number.
Use this demonstration of the futility of statistics at your own risk. Don't blame me for the bread rolls and assorted cutlery that are thrown at you.