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Cao Chong weighs the elephant
When we want to know how much we weigh, we stand on a scale. But when something is very big, like an elephant, how do we weigh it? A long time ago, the famous warlord, Cao Cao, faced this question.
One day, Cao Cao received an elephant as a gift. "What a big animal! How much does it weigh?" Cao Cao asked. No one could answer his question because no scale was big enough.
Cao Cao's six-year-old son Cao Chong said, "Father, let me try!"
Cao Chong asked a man to get the elephant onto a boat on a river. The boat went down a little, and Cao Chong marked the water level on the boat. He then asked some strong men to put rocks on the boat. When the water reached the mark, Cao Chong said, "Stop!"
"Let's weigh these rocks, and add their weights together. Then we'll know the weight of the elephant," said Cao Chong.
Finally, they found out the weight of the elephant. Cao Cao was very happy.