Question

If 5 apples in a barrel of 25 apples are rotten, what is the expected number of rotten apples in a random sample of 2 apples?

Its a probability Question!!! :S

Answer 1

Let x = number of rotten apples in sample of 2 apples

The table shows the probabilities of finding 0, 1 or 2 rotten apples in a random sample of 2 apples. These probabilities were caculated using the hypergeometric distribution.
The expected number is given by:\[E(X)=\sum_{}^{}x p(x)\]
E(X) = (0 * 0.633) + (1 * 0.333) + (2 * 0.033) = 0.4