Question 1130193
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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)  {{{(1/2)*(1/2)*(1/2)*(1/2)}}} = {{{1/2^4}}} = {{{1/16}}}.



(b)  1 - P(all 4 children are girls) = {{{1}}} - {{{1/2^4}}} = {{{1 - 1/16}}} = {{{15/16}}}.



(c)  {{{C[4]^2*(1/2)*(1/2)*(1/2)*(1/2)}}} = {{{((4*3)/2)*(1/16)}}} = {{{6/16}}} = {{{3/8}}}.
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