SOLUTION: Problem: A jar contains seven black buttons and seven brown buttons. If nine buttons are picked at random, what is the probability that at most five of them are black?
My Attemp
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My Attemp
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Question 1070126: Problem: A jar contains seven black buttons and seven brown buttons. If nine buttons are picked at random, what is the probability that at most five of them are black?
My Attempt: I found the total ways to pick 9 out of 14 using the combination formula, 2002. I then using combination listed the possible ways to pick 1,2,3,4 and 5 black buttons.
1:49
2:441
3:1125
4:1125
5:441
Adding these gives me a number greater than 2002...but probability must be less than 1... Where might have I went wrong? I know the correct answer is 124/143 due to the answer key. Thanks in Advance! Answer by Fombitz(32388) (Show Source):
