document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1086245>Question 1086245</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 	Samsung wants to know how long cell phone owners keep their phones before upgrading.  A simple random sample of 23 cell phone owners results in a mean of 2.64 years and a standard deviation of 0.71 years.  Assume the sample is drawn from a normally distributed population.  <BR>\n" );
document.write( "	Find the 95% confidence interval of the population mean. \r<BR>\n" );
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document.write( "	If you worked for Samsung and decided you wanted to be 99% confident that the sample mean is within 0.25 years of the population mean, how large of a sample would you need to take?  Assume that &#963;=0.71 for this calculation.\r<BR>\n" );
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document.write( "Explain why the population parameter may NOT follow a normal distribution.  Would you expect the data to show a positive or negative skew?  Explain.  If the data were not normally distributed, how would this affect the calculations for the confidence interval?<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 #700646 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=700646\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> They want to get rid of them after they ignite. </SPAN>\n" );
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