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Children and probability.

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by prindaroy » Sun Aug 16, 2009 2:16 pm
Answer is D.

4c2 * (1/2)^2 * (1/2)^2
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by clar » Sun Aug 16, 2009 2:22 pm
could you pls elaborate further!
thanks!
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by tohellandback » Sun Aug 16, 2009 6:27 pm
IMO D

either 2 boys 2 girls
or, 3 boys 1 girl
or, 4 boys

2 boys selected in 4C2 ways

total prob=4C2{(1/2)^2*(1/2)^2 + (1/2)^3 *1/2 + (1/2)^4}

=4C2 * 1/16= 3/8
The powers of two are bloody impolite!!
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