This weekend on NPR's Car Talk they had a math puzzler. Here's a short retelling of the puzzle:
In a particulcar club you can get a free drink if you know the code. The waitress gives you a number and if you give the right number back, you get a free coke. Here's what you observe:
She says 6. Someone says 3 and gets a free drink.
She says 12. Someone says 6 and gets a free drink.
She says 14. Someone says 8 (not 7) and gets a free drink.
She says 22. What do you say to gedt a free coke?