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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I didn't use the normal approximation there-- that's obvious--I used the binomial itself.

我显然并没有用到正态分布,我用了二项分布

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