A bag has 4 red marbles, 5 white marbles, 6 blue marbles, and 7 green marbles. Three marbles are drawn from the bag (without replacement). What is the probability that they are all the same color?
Assume all the marbels are different.
the number of ways that three blues can be chosen is 6C3
the number of ways that three white can be chosen is 5C3
the number of ways that three red can be chosen is 4C3
the number of ways any 3 can be chosen is 18C3
Can you finish it?