document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1079029>Question 1079029</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1.If a couple wants to have three or four children, including exactly two girls, what is the probability that their wish will come true?\r<BR>\n" );
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document.write( "The solution is 3/4 but Im not getting that please help\r<BR>\n" );
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document.write( "shonhardy@yahoo.com </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #693393 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=693393\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Consider two applications of the binomial probability distribution<BR>\n" );
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document.write( "Probability(k successes out of n trials) = nCk * p^k * (1-p)^(n-k)<BR>\n" );
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document.write( "nCk is (n! / (k! * (n-k)!)<BR>\n" );
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document.write( "For this problem p is 0.5 and n is 3 or 4<BR>\n" );
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document.write( "P(exactly 2 girls in 3 or 4 children) = P(2 girls out of 3 children) + P(2 girls out of 4 children) = 0.375 + 0.375 = 0.75<BR>\n" );
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