In a large on-the-job training program, half of the participants are female and half are male. In a random sample of 4 participants, what is the probability that an investigator will draw at least 2 male?
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Probability of selecting 4 female = (½)^4 = 1/16
Probability of selecting 3 female, 1 male = 4(½)^3(½) = 4/16
Total probability of selecting 0 or 1 male = 5/16.
Therefore probability of selecting 2 or more males = 1 - 5/16 = 11/16
Probability of selecting 3 female, 1 male = 4(½)^3(½) = 4/16
Total probability of selecting 0 or 1 male = 5/16.
Therefore probability of selecting 2 or more males = 1 - 5/16 = 11/16
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0.5625, I think this is correct