Suppose that in a population of 1000 there are 300 defective

Suppose that in a population of 1000 there are 300 defective items and 700 items that are not defective. If you are selecting two items at random from this population, what is the probability they will both be defective?

Solution

As 2 << 300, 700, then we can approximate the events to be independent.

Here,

P(defective) = 300/1000 = 0.3

Thus,

P(both defective) = 0.3^2 = 0.09 [ANSWER]