There are 10 yellow, 6 green, 9 orange, and 5 red cards in a stack of cards turned facedown. Once a card is selected, it is not replaced. Determine the probability. P (two green cards)

30 cards all together so the first turn you have a 1 out of 5 chances of getting a green card. So now there is only 29 cards left face down now you have a 6 out of 29 chance of turning over a green card. Now multiply them together

1/5 x 6/29 = 6/145. So to get 2 green cards you have a probability of 6 out of 145.