Riddle: Marge and Lucille were best of friends, but both of them were highly competitive. One day they entered a grueling 50-mile bicycle race along with a large group of other contestants. Lucille was the more experienced of the two riders, but throughout the race, Marge was always out in front of her. Not once did she allow Lucille to pass her, but Lucille's fiery, competitive spirit would not be quenched, as she never let Marge out of her sight for even one instant. Even after 50 long miles, Marge and Lucille were only separated by a couple of feet, with Marge finally passing the finish line less than one second ahead of Lucille. Neither racer won, but they both finished in the top ten of all the competitors. After the race, Lucille was asked about her competing with her friend Marge. All Lucille would say was, "I couldn't have passed her, even if I had wanted to. In fact, it was impossible." What led Lucille to make such a bizarre statement?"
Answer: Marge and Lucille had been participating in a tandem bicycle race (bicycles built for two people).