SOLUTION: Suppose the probability that a person has red hair is .15. If 7 people are selected at random, what is the probability that a) all 7 have red hair? b) at least 1 has red hair?

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Question 664411: Suppose the probability that a person has red hair is .15. If 7 people are selected at random, what is the probability that
a) all 7 have red hair?
b) at least 1 has red hair?
show your work.

Answer by htmentor(1343) About Me  (Show Source):
You can put this solution on YOUR website!
P(7 have red hair) = 0.15^7 = 1.71E-6
P(at least 1 have red hair) = 1 - P(none have red hair)
P(none) = 0.85^7 = 0.321
So the probability that at least one has red hair = 1 - 0.321 = 0.679