If the probability is 1 in 1,000 that a house burns down and there are 1,000 houses, then the probability that they all burn down is 1/1000 to the 1000th power, which is virtually zero.

如果一栋房子着火的概率是千分之一,然后假设有1000栋房子,那么这一千栋房子全都着火被烧掉的概率,就等于千分之一的一千次方,基本上就是0了

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