Answer:
18/95
Step-by-step explanation:
At first, there are 20 cubes, 9 of which are black. The probability that the first cube is black is P = 9/20.
After the first cube is selected, there are 19 cubes left, 8 of which are black. The probability that the second cube is black is P = 8/19.
The total probability is:
P = (9/20) (8/19)
P = 18/95
