<span>The Total number of Marbles contained in the Box is as follows:
5 (Red) + 8 (green) + 4 (blue) + 3(yellow) = 20 Marbles
The Probability of selecting the first Marble (Red) is 5/20
Then 19 Marbles will be left.
The probability of selecting the second Marble green is 8/19
Since the first marble was not replaced then the probability of selecting a red marble and then a green marble is = 5/20 * 8/19 = 2/19.</span>