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一个城市的月用电量有 mu = 500 度电和 sigma = 80 度电。对于 n = 100 个随机抽取的住户,计算 P(\bar X > 510) 。
一个城市的月用电量有 mu = 500 度电和 sigma = 80 度电。对于 n = 100 个随机抽取的住户,计算 P(\bar X > 510) 。
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