If you follow through from the independent theory, there's one of the basic relations in probability theory-- it's called the binomial distribution.

如果继续往下看,在概率论里有一个基本的概念,叫做二项分布

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It uses the binomial distribution to calculate the probability of getting any specific number of accidents.

保险公司就可以用二项分布公式,来计算特定数目事故发生的概率

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