What is the variance of a Hypergeometric distribution H(N,K,n)H(N, K, n)H(N,K,n)?
nKN(1−KN)n \frac{K}{N} (1-\frac{K}{N})nNK(1−NK)
nKN(1−KN)N−nN−1n \frac{K}{N} (1-\frac{K}{N}) \frac{N-n}{N-1}nNK(1−NK)N−1N−n
nKNN−KNn \frac{K}{N} \frac{N-K}{N}nNKNN−K
nKNN−1N−nn \frac{K}{N} \frac{N-1}{N-n}nNKN−nN−1