Question

A bag contains six real diamonds and five fake diamonds. If six diamonds are picked from the bag at random what is the probability that at most four of them are real?

Answer 1

Answer:

((6 choose 4) * (5 choose 2) + (6 choose 5) * (5 choose 1) + (6 choose 6) * (5 choose 0)) / (11 choose 6) = 181/462 = 0.3918