Thread: Simple Question
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Old 10-10-2005, 03:21 PM
BruceZ BruceZ is offline
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Default Re: Simple Question

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For some reason I can't get the right answer for this.

Suppose a vase has 15 balls, of which 8 are red and seven are black.

In how many ways can 5 balls be chosen so that at least two are red?

[/ QUOTE ]

C(15,5) - C(7,5) - 8*C(7,4) = 2702.
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