document.write( "Question 435553: Hi!\r
\n" ); document.write( "\n" ); document.write( " I have a probability question: A family has three children. What is the probability that one is boy given that one is a girl?\r
\n" ); document.write( "\n" ); document.write( "Thank you for your help!
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Algebra.Com's Answer #301421 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
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
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\n" ); document.write( "There are 7 sample points where there is at least 1 girl. Of these seven , there are 6 elements where there is at least 1 boy. Hence the probability that one is boy given that one is a girl is 6/7.
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