document.write( "Question 1155751: Given a family with four ​children, find the probability of the event.
\n" ); document.write( "The oldest is a girl and the youngest is a boy​, given that there is at least one boy and at least one girl. \n" ); document.write( "
Algebra.Com's Answer #778394 by Edwin McCravy(20063)\"\" \"About 
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document.write( "There are 16 cases of a family with 4 children, (no twins)\r\n" );
document.write( "We eliminate by lining through, the ones that are not given.\r\n" );
document.write( "So that leaves 14.\r\n" );
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document.write( "First   Second    Third   Youngest    Given?   Success?\r\n" );
document.write( "Born     Born      Born\r\n" );
document.write( "  B        B         B        B        No        \r\n" );
document.write( "  B        B         B        G        Yes        No\r\n" );
document.write( "  B        B         G        B        Yes        No\r\n" );
document.write( "  B        B         G        G        Yes        No\r\n" );
document.write( "  B        G         B        B        Yes        No\r\n" );
document.write( "  B        G         B        G        Yes        No\r\n" );
document.write( "  B        G         G        B        Yes        No\r\n" );
document.write( "  B        G         G        G        Yes        No\r\n" );
document.write( "  G        B         B        B        Yes        Yes\r\n" );
document.write( "  G        B         B        G        Yes        Yes        \r\n" );
document.write( "  G        B         G        B        Yes        Yes\r\n" );
document.write( "  G        B         G        G        Yes        Yes\r\n" );
document.write( "  G        G         B        B        Yes        Yes\r\n" );
document.write( "  G        G         B        G        Yes        Yes\r\n" );
document.write( "  G        G         G        B        Yes        Yes\r\n" );
document.write( "  G        G         G        G        No \r\n" );
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document.write( "So that's 7 successes out of 14, so the probability is 7/14 which\r\n" );
document.write( "reduces to 1/2.\r\n" );
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document.write( "Edwin
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