document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1189096>Question 1189096</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The mean birth weight for Ethiopian babies is μ =3.1 kg with sd (σ=0.5 kg)<BR>\n" );
document.write( "A) What weight values encompass the 95% newborns? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #820332 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=820332\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the mean is 3.1 kg and the standard deviation is .5 kg.<BR>\n" );
document.write( "with a two tailed confidence interval of 95%, the critical z-score will be plus or minus 1.96\r<BR>\n" );
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document.write( "that leave a 2.5% tail on both ends of the confidence interval  that are outside the confidence interval.\r<BR>\n" );
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document.write( "the z-score formula is:\r<BR>\n" );
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document.write( "z = (x - m) / s\r<BR>\n" );
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document.write( "in this case:\r<BR>\n" );
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document.write( "z is the z-score<BR>\n" );
document.write( "x is the sample mean<BR>\n" );
document.write( "m is the population mean<BR>\n" );
document.write( "s is the population standard deviation\r<BR>\n" );
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document.write( "you get 1.96 = (x - 3.1) / .5 and -1.96 = (x - 3.1) / .5\r<BR>\n" );
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document.write( "when z = 1.96, solve for x to get x = 1.96 * .5 + 3.1 = 4.08.\r<BR>\n" );
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document.write( "when z = -1.96, solve for x to get x = -1.96 * .5 + 3.1 = 2.12\r<BR>\n" );
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document.write( "at 95% confidence interval, the weight of babies will be between 2.12 and 4.08 kg.\r<BR>\n" );
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document.write( "what they says is that, approximately 95% of the samples taken will have a sample mean between 2.12 and 4.08 kg.\r<BR>\n" );
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document.write( "here's what it looks like on a graph.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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