number of draws versus odds to get 6 of 72 items update - changing the problem statement: You have a jar filled with 66 white, and 6 unique balls: 1 red, 1 blue, 1 green, 1 purple, 1 yellow, and 1 cyan ball. You draw the balls one at a time and return them each time, recording what you've drawn. What is the average number of draws before you see all 6 unique colored balls at least once? Using a program to test this, it seems that about 176 draws are needed. I could modify the program to determine the average success rate versus number of draws to get the answer to the original problem statement, but what I really wanted was the average number of draws for success. I could probably do a standard deviation on this, but that's not really needed either.