Question 1157073
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<pre>

You are given this configuration for children


    X    B   Y


where X and Y stand for unknown gender and B stands for boy (which is the middle child)


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.


It is your "sample space" in this problem.


You are also given that the family has 2 boys.


It means, that only these two configurations suits for the condition


    B   B   G
or
    G   B   B.


So, there are 2 favorable configurations.


The probability under the question is the ratio "favorable/total", which in this case takes the form  {{{2/4}}} = {{{1/2}}}.   <U>ANSWER</U>
</pre>

Solved.


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On conditional probability and for "sample of space", look into the lessons

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/Probability-and-statistics/Using-sample-space-to-solve-Probability-problems.lesson>Using sample space to solve Probability problems</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/Probability-and-statistics/Conditional-probability-problems.lesson>Conditional probability problems</A> 

in this site.


Also, &nbsp;you have this free of charge online textbook in ALGEBRA-II in this site

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-II - YOUR ONLINE TEXTBOOK</A>.


The referred lesson is the part of this online textbook under the topic &nbsp;"<U>Solved problems on Probability</U>". 



Save the link to this textbook together with its description


Free of charge online textbook in ALGEBRA-II
https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson


into your archive and use when it is needed.