Abox contains 5 red marbles, 8 green marbles, 4 blue marbles, and 3 yellow marbles. if 2 marbles are randomly selected without replacement, what is the probability that a red marble is selected and then a green marble is selected?

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.

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.