Final answer:
The probability of randomly selecting a red marble, setting it aside, and then randomly selecting another red marble from the bag is 5/33.
Step-by-step explanation:
To find the probability of randomly selecting a red marble from the bag, setting it aside, and then randomly selecting another red marble, we need to consider the total number of marbles and the number of red marbles.
In the bag, there are 5 red marbles, 3 white marbles, and 4 blue marbles. After removing one red marble, there are 4 red marbles remaining in the bag.
The probability of selecting a red marble on the first draw is 5/12, and the probability of selecting another red marble on the second draw is 4/11. To find the overall probability, we multiply these two probabilities together: (5/12) * (4/11) = 20/132 = 5/33.