Question

Xavier has a bag of 20 marbles. 8 are blue, 7 are red, and 5 are green. Xavier pulls out a marble, records what color it is, and puts it back. He then selects another marble and records its color What is the probability of pulling out a blue marble and then a green marble?

Answer 1

0.1

Explanation:

chance of pulling out a blue marble can be described as 8 equally probable outcomes (blue marbles) out of 20 equally probable outcomes (all marbles).

Similarly, the chance of pulling out a green marble is 5 out of 20.

In total, we have 8*5 (combinations of blue then green) outcomes out of 20*20 (any two marbles):

8*5 / (20*20) = 40 / 400 = 1/10 = 0.1