Question

Several million lottery tickets are sold, and 21% of the tickets are held by men. Suppose you select a random sample of people and let X represent the number of people in your sample for which are men with winning tickets. What type of random variable is X?

hypergeometric

Bernoulli

poisson

uniform

Answer 1

hypergeometric

Explanation:

For each winning ticket, there are only two possible outcomes. Either it is held by a men, or it is not.

There is a set number of X, and as the number of winning tickets decrease, the probability of a winning ticket being held by a men can decrease or increase. This is a characteristic of the hypergeometric distribution.