document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1185302>Question 1185302</A>: <I><SPAN STYLE=\"word-break: break-all;\"> we want to estimate the mean of a population a random sample of subjects is selected and the sample mean is competed what is the probability that the sample mean is within 3 units of the true mean if the standard error is 1.8 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #816147 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=816147\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> i get the following:\r<BR>\n" );
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document.write( "if the sample mean is within 3 units of the population mean and the standard error is 1.8, then:\r<BR>\n" );
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document.write( "the lower z-score is equal -3/1.8 = -1.6666667 and the higher z-score is equal to 3/1.8 = 1.66666667.\r<BR>\n" );
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document.write( "the area under the normal distribution curve between these two z-score values is .9044193393.\r<BR>\n" );
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document.write( "that is the probability that the true population mean will be within 3 units of the sample mean.\r<BR>\n" );
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document.write( "as an example of what i think is the answer, assume any sample mean, such as 5342.\r<BR>\n" );
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document.write( "if the real population mean can be as much as 3 units below this, then the lower x-score is 5339.\r<BR>\n" );
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document.write( "if the real population mean can be as much as 3 units above this, then the upper x-score is 5345.\r<BR>\n" );
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document.write( "to find the lower and higher z-scores, use the z-score formula to get:\r<BR>\n" );
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document.write( "lower z = (5339 - 5342) / 1.8 = -3/1.8 = -1.66666667.\r<BR>\n" );
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document.write( "higher z = (5345 - 5342) / 1.8 = 3/1.8 = 1.66666667.\r<BR>\n" );
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document.write( "the area between these two z-scores is the same as shown above.\r<BR>\n" );
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document.write( "that is equal to .9044193393.\r<BR>\n" );
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document.write( "based on these figures, the sample mean can be anything, as long as the standard error is 1.8 and the lower and higher figures are 3 units below and above that mean.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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