They had to divide by hand and so they didn't like the number 365, so they thought, let's just round it to 360.

他们必须手工计算,所以不太喜欢365,所以他们就近似成360

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To actually apply this it helps to go to something called the normal approximation to the binomial, because it's kind of difficult to compute this formula.

在实际应用这些公式的时候,需要运用二项分布的正态近似定理,因为二项分布公式的值很难计算

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