SOLUTION: If the probability a child is a boy is 1/2 and sex is independent from child to child, what is the probability in a family of four children that a. All will be boys? b. At lea

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Question 1130193: If the probability a child is a boy is 1/2 and sex is independent from child to child, what is the probability in
a family of four children that
a. All will be boys?
b. At least one will be a boy?
c. There will be the same number of boys as girls?
Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
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If the probability a child is a boy is 1/2 and sex is independent from child to child, what is the probability in
a family of four children that
a. All will be boys?
b. At least one will be a boy?
c. There will be the same number of boys as girls?
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(a)  %281%2F2%29%2A%281%2F2%29%2A%281%2F2%29%2A%281%2F2%29 = 1%2F2%5E4 = 1%2F16.



(b)  1 - P(all 4 children are girls) = 1 - 1%2F2%5E4 = 1+-+1%2F16 = 15%2F16.



(c)  C%5B4%5D%5E2%2A%281%2F2%29%2A%281%2F2%29%2A%281%2F2%29%2A%281%2F2%29 = %28%284%2A3%29%2F2%29%2A%281%2F16%29 = 6%2F16 = 3%2F8.