Year after year Stumpy and Martha attended the fair in their home state, and every summer it was the same story: Stumpy was tantalized by the old-fashioned bi-plane in which anybody could take a ride for ten dollars, and Martha was disgusted by such an obvious waste of money. "Ten dollars is ten dollars," she would always say. And Stumpy would go home without his airplane ride. 

One year Stumpy said, "Martha, there's that bi-plane again. I am 81 years old and this year I want to go for a ride." Martha bristled, "There you go again. Don't you realize that ten dollars is ten dollars?" At this point the man who owned the bi-plane, and who had heard this conversation as far back as he could remember, intervened. "Listen, you two, I'll make you a deal. I'll give you both a ride for free if you…