There a 4 black marbles and 2 white marbles in a bag. what is the probability of choosing a black marble, not replacing it, then choosing a white marble ?

Question

how do you find the probability of this 

Answer 1

If two events, A and B are independent then the joint probability is
P(A and B) = P(A ∩ B) = P(A) P(B)

 

Does taking a black marble out of the bag effect the probability of getting a white on the next try?  No.

There are 6 total marbles, so the event of getting a black on on the 1st try is 4 out of 6.

There are now 5 marbles in the bag and 2 white so for the second event there always a probability of 2 out of 5.

Can you take it from there?