document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=216702>Question 216702</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A university wants to estimate the average amount of money that students spend on textbooks in a semester.  It takes a random sample of 45 students and finds that an average amount of money spent was $282 with a standard deviation of $21.  Find a 95% confidence interval estimate for the true mean amount of money spent on textbooks in a semester. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #163654 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=163654\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A university wants to estimate the average amount of money that students spend on textbooks in a semester. It takes a random sample of 45 students and finds that an average amount of money spent was $282 with a standard deviation of $21. Find a 95% confidence interval estimate for the true mean amount of money spent on textbooks in a semester.<BR>\n" );
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document.write( "sample mean = 282<BR>\n" );
document.write( "standard error = 1.96 = 6.1358...<BR>\n" );
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document.write( "95% CI: 282-6.1358 < u < 282 + 6.1358<BR>\n" );
document.write( "95% CI: 275.86 < u < 288.14<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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