An Urn Contains Marbles Of Four Colors. A box contains 4 black marbles 7 red marbles and 8 green marbles. Three marbles are selected at random and without replacement. An urn contains a very large number of marbles of four different colors.
See pólya urn model. Three marbles are selected at random and without replacement.
In fact 3 different objects can be arranged in 3 6 different orders so each of those 24 sets of 3 marbles of 3 different colors can be drawn in 6 different orders.
4 6 5 120 of possible triples. All but 45 are yellow. Three marbles are selected at random and without replacement. A box contains 4 black marbles 7 red marbles and 8 green marbles.
