document.write( "Question 435571: A family has three children. What is the probability that the first is a boy given that one is a girl? \n" ); document.write( "
Algebra.Com's Answer #301426 by robertb(5830)\"\" \"About 
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The following list gives the sample space (assuming no multiple births!)
\n" ); document.write( "BBB
\n" ); document.write( "BBG
\n" ); document.write( "BGB
\n" ); document.write( "BGG
\n" ); document.write( "GBB
\n" ); document.write( "GBG
\n" ); document.write( "GGB
\n" ); document.write( "GGG\r
\n" ); document.write( "\n" ); document.write( "There are 7 sample points where there is at least 1 girl. Of these seven , there are 3 elements where the first child is a boy. Hence the probability that the first is a boy given that one is a girl is 3/7.
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