document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=427437>Question 427437</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Using normal approximation, what is an estimation of the probability of getting more than 51 girls in 100 births, assuming that boys and girls are equally likely. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #297327 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=297327\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Using normal approximation, what is an estimation of the probability of getting more than 51 girls in 100 births, assuming that boys and girls are equally likely.<BR>\n" );
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document.write( "mean = np = 100(1/2) = 50<BR>\n" );
document.write( "std = sqrt(npq) = sqrt(25) = 5<BR>\n" );
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document.write( "z(49.5) = (49.5-50)/5 = -0.5/5 = -0.1<BR>\n" );
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document.write( "z(100.5) = (100.5-50)/5 = 10.1<BR>\n" );
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document.write( "P(51< x <=1) = P(-0.1< z <= 10.1) = 0.5398<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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