What is the probability of choosing blue marble followed by a green marble from a bag containing 5 blue 5 green and 5 red marbles?

The probability of choosing a blue marble is 5 in 15 or 1 in 3. The probability of then choosing a green marble is 5 in 14. (One is missing) Multiply the two probabilities and you get 5 in 42.(P = 0.1190... about 12%).