Find the expected value of the random variable in the experiment.
-A bag contains six marbles, of which four are red and two are blue. Suppose two marbles are chosen at random and $\mathrm{X}$ represents the number of red marbles in the sample.
A) 1.4
B) 1.33
C) .933
D) 1

Question

Quizplus · Accepted Answer

The probability of choosing a red marble on the first draw is 4/6 = 2/3. The probability of choosing a red marble on the second draw is 3/5. The probability of choosing two red marbles is (2/3) * (3/5) = 6/15 = 2/5. The expected value of X is 2 * (2/5) = 4/5 = 0.8.

Find the Expected Value of the Random Variable in the Experiment