Question

2. Ajar contains 10 marbles, 6 marbles are red, and 4

marbles are blue. If 2 marbles are chosen one at a time
without replacement, what is the probability that the first
marble will be blue and the second marble will be red?
A: 3/16 B: 6/25 C: 1/8 D : 12/45
Independent or Dependent:
Final Answer:

Answer 1

A

Explanation:

Note that there are 16 total marbles. A is simply a set of sequential events. On the first, you have 10/16 chances to draw a red. Supposing this red is not replaced, the chance of drawing a second red will be 9/15; therefore, the probability of A is (10/16) * (9/15) = 0.375. Event B is translated into 2 events: Blue + (White or Red) or (White or Red) + Blue. The probabilities of each of these events, added together would be (2/16) * (14/15) + (14/16) * (2/15) = 0.2333333333; therefore, A is more probable.