document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1182137>Question 1182137</A>: <I><SPAN STYLE=\"word-break: break-all;\"> According to the growth chart that doctors use as a reference, the heights of two-year-old boys are normally distributed with mean 34.5 inches and standard deviation 1.3 inches. If six two-year old boys are selected, what is the probability that their average height will be between 34.1 and 35.2 inches.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #812129 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=812129\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> this is a z-test<BR>\n" );
document.write( "z=(x bar-mean)/sigma/sqrt(n)<BR>\n" );
document.write( "=(34.1-34.5)/1.3/sqrt(6)<BR>\n" );
document.write( "=-0.4*sqrt(6)/1.3<BR>\n" );
document.write( "=-0.753<BR>\n" );
document.write( "and similarly, z=0.7*sqrt(6)/1.3=1.319<BR>\n" );
document.write( "the probability z is between those two values is 0.6806<BR>\n" );
document.write( "or<BR>\n" );
document.write( "calculator 2ndVARS2nnormal cdf(34.1,35.2,34.5,(1.3/sqrt(6)))<BR>\n" );
document.write( "=0.6809 (less rounding so slightly more accurate.  Find out whether the z-value is to 2,3, or more decimal places. </SPAN>\n" );
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