document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=572774>Question 572774</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A couple wants to start a family. A doctor tells the couple based on many factors, the probability distribution for possible birts is given. G for girl and B for boy. Assume the probabilities don't change for any reason. \r<BR>\n" );
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document.write( "X  P(X=x)     G 5/9     B 3/8\r<BR>\n" );
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document.write( "What is the probability that within the first 7 births the family will have at least 2 boys? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #368555 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=368555\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> P(X=x) G 5/9 B 3/8 <BR>\n" );
document.write( "What is the probability that within the first 7 births the family will have at least 2 boys?<BR>\n" );
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document.write( "Ans: P(2<= x <=7) = 1 - P(0<= x <=1) = 1 - [P(x = 0)+P(x = 1)]<BR>\n" );
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document.write( "= 1 - [(3/8)^7 + 7C1(5/9)(3/8)^6]<BR>\n" );
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document.write( "= 1 - [0.001+ 0.0108]<BR>\n" );
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document.write( "= 1 - [0.0109]<BR>\n" );
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document.write( "= 0.9891<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "=================== </SPAN>\n" );
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