Cao Chong Weighs an Elephant

How much does an elephant weigh? How do you know? How would you know if you didn't have a modern scale? Six-year-old Cao Chong, the most famous child prodigy in Chinese history, faced just this problem! Chong watches as the prime minister's most trusted and learned advisors debate different methods. The principle of buoyancy and a little bit of creative thinking help this boy come up with a solution.