## Hypergeometric distribution

A lot of items contains defectives, and are selected randomly and inspected. How should the value of be chosen so that the probability that at least one defective item turns up is 0.9? Apply your answer to the following cases:- and ;
- and .

Suppose that we have a lot of size containing defectives. If we sample and inspect random items, what is the probability that we will find defectives in our sample? This probability is called a hypergeometric distribution, and expressed by

Given and in the hypergeometric distribution, the smallest value can be determined so that .