Given:
there are 6 red marbles 3 blue marbles and 6 green marbles in the Box
So, the total marbles = 6 + 3 + 6 = 15
The probability of drawing a red marble = 6/15
After drawing the red, the remaining marbles = 14
The probability of drawing a green marble = 6/14
So, the probability of drawing a red marble and then a green marble without replacing the first marble =
So, the answer will be 0.171