SOLUTION: An urn contains 10 numbered balls, of which 6 are red and 4 are blue. A sample of 4 balls is to be selected. How many samples contain at least 3 red balls?
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-> SOLUTION: An urn contains 10 numbered balls, of which 6 are red and 4 are blue. A sample of 4 balls is to be selected. How many samples contain at least 3 red balls?
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Question 470963: An urn contains 10 numbered balls, of which 6 are red and 4 are blue. A sample of 4 balls is to be selected. How many samples contain at least 3 red balls? Answer by ewatrrr(24785) (Show Source):
Hi,
Note: The probability of x successes in n trials is:
P = nCx* where p and q are the probabilities of success and failure respectively.
In this case p = .6(red)& q = .4
nCx = n = 4
P(3 or 4 red) = P(3red) + P(4red) = 4(.6)^4*.4 + (.6)^4 = .4752
sry, did not read it properly:
47.52% of the samples contain at least 3 red.
