A bag holds 2 yellow, 1 green, and 2 red marbles. If you were to draw a marble from the bag 150 times, and replace it after each draw, how many yellow marbles would you expect to draw?

A. 50
B. 60
C. 30
D. 120

1 answer

The probability of drawing a yellow marble from the bag is 2/5. If you draw from the bag 150 times with replacement, the expected number of yellow marbles you would get is:

Expected value = probability of yellow marble x number of draws

Expected value = (2/5) x 150
Expected value = 60

Therefore, the answer is B. You would expect to draw 60 yellow marbles.