Find the probability for the experiment of drawing two marbles at random (without replacement) from a bag containing four green, two yellow, and three red marbles. both marbles are red.

1/12. there are nine total marbles, 3 of which are red. 3/9 simplifies to 1/3. So the first draw you have a one third chance of drawing a red marble. after that, there are 8 marbles, 2 of which are red. 2/8 simplifies to 1/4. you then multiply 1/3 and 1/4 to get your answer of 1/12.