请以一个段落格式并以"Once upon a time"开头，计算在某个区域有1000棵树时，平均每公顷有几棵树？数据提供了区域面积是5公顷，请求输出只包含计算答案，不带单位。
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Once upon a time, in a land covered with lush greenery, it was discovered that within a 5-hectare area, there were 1000 trees. With a quick calculation, we find that an average of 200 trees populate each hectare.
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