Dana is going to draw marbles out of the bag. In the bag, there are 10 marbles. There are 4 black marbles, 5 white marbles, and 1 red marble. Dana choooses two marbles. After choosing the first one she put it back in the bag before choosing the second marble. What is the probability that both marbles she chooses are black? *

1 answer

4 black out of 10 marbles, so
P(black) = 4/10
the two draws are independent, so multiply the probabilities.