Answer: 1/4
Explanation:
To find the probability that Robbie will pull a blue marble out of the bag, we need to first determine the total number of marbles in the bag. Since there are 2 blue marbles, 4 red marbles, and 2 yellow marbles, the total number of marbles in the bag is 2 + 4 + 2 = 8.
Next, we need to determine the number of blue marbles in the bag. Since there are 2 blue marbles, the number of blue marbles in the bag is 2.
Finally, we can use these numbers to calculate the probability that Robbie will pull a blue marble out of the bag. The probability is equal to the number of blue marbles divided by the total number of marbles, which is 2 / 8 = 1/4. Therefore, the probability that Robbie will pull a blue marble out of the bag is 1/4.