A bag contains 3 red marbles, 7 blue marbles, and 2 green marbles. What is the probability of choosing a blue marble when one marble is drawn?
To find the probability of choosing a blue marble, we need to find the total number of blue marbles and then divide by the total number of marbles in the bag.
The total number of blue marbles in the bag is 7. The total number of marbles in the bag is 3 (red marbles) + 7 (blue marbles) + 2 (green marbles) = 12.
Therefore, the probability of choosing a blue marble is 7/12.