So I'm being asked: A box contains 10 red marbles, 9 green marbles, and 7 black marbles. A sample of 11 marbles is to be picked from the box:
C(26,11) - C(10,0) * C(16,11) = at least 1 red.
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(A)= C(10,5)*C(16,6)
(B)= C(7,3)*C(19,8)
(C)= C(10,5)*C(7,3)*(9,4)
I add A and B and subtract C and get my answer.
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- [FONT=verdana, helvetica, sans-serif]How many samples contain at least 1 red marble?[/FONT]
C(26,11) - C(10,0) * C(16,11) = at least 1 red.
- How many samples contain exactly 5 green marbles or exactly 3 black marbles?
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(A)= C(10,5)*C(16,6)
(B)= C(7,3)*C(19,8)
(C)= C(10,5)*C(7,3)*(9,4)
I add A and B and subtract C and get my answer.
- How many samples contain exactly 7 red marbles or exactly 6 green marbles?
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