document.write( "Question 1157073: A family tree has three children. What is the probability that the family has 2 boys and a girl given the middle child is a boy? \n" ); document.write( "

Algebra.Com's Answer #779865 by ikleyn(52797) $\"\"$ $\"About$

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document.write( "You are given this configuration for children\r\n" );
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document.write( "    X    B   Y\r\n" );
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document.write( "where X and Y stand for unknown gender and B stands for boy (which is the middle child)\r\n" );
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document.write( "Here X and Y may have 2 values X= B or G, and  Y = B or G, so there are 4 possible configurations with \"B\" in the center.\r\n" );
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document.write( "It is your \"sample space\" in this problem.\r\n" );
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document.write( "You are also given that the family has 2 boys.\r\n" );
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document.write( "It means, that only these two configurations suits for the condition\r\n" );
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document.write( "    B   B   G\r\n" );
document.write( "or\r\n" );
document.write( "    G   B   B.\r\n" );
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document.write( "So, there are 2 favorable configurations.\r\n" );
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document.write( "The probability under the question is the ratio \"favorable/total\", which in this case takes the form   = .   ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "--------------------\r
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\n" ); document.write( "\n" ); document.write( "On conditional probability and for \"sample of space\", look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Using sample space to solve Probability problems\r
\n" ); document.write( "\n" ); document.write( "    - Conditional probability problems \r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-II in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lesson is the part of this online textbook under the topic \"Solved problems on Probability\". \r
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\n" ); document.write( "\n" ); document.write( "Save the link to this textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-II
\n" ); document.write( "https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "into your archive and use when it is needed.\r
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