Question

What is the probability of drawing yellow marble followed by a red marble from a bag containing 12 yellow marbles, 16 red marbles, and 15 green marbles if the first marble is not replaced?

Answer 1

12 +16 +15 = 43 total marbles

12 are yellow so first pick you have 12/43 probability of picking yellow

 without replacement there would be 42 marbles left

 there are 16 red ones so you  have a 16/42, reduces to 8/21 probability of picking red

 probability of picking yellow then red =

12/43 x 8/21 = 96/903, reduces to 32/301 probability