document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=223767>Question 223767</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A school social worker wishes to estimate the mean amount of time each week that high school students spend with friends. She obtains a random sample of 1175 high school students and finds that the mean weekly time spend with friends is 9.2 hours. Assuming the population standard deviation amount of time soend with friends is 6.7 hours, construct and interpret a 90% confidence interval for the mean time spent with friends each week </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #167259 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=167259\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A school social worker wishes to estimate the mean amount of time each week that high school students spend with friends. <BR>\n" );
document.write( "She obtains a random sample of 1175 high school students and finds that the mean weekly time spent with friends is 9.2 hours. <BR>\n" );
document.write( "Assuming the population standard deviation amount of time spent with friends is 6.7 hours, construct and interpret a 90% confidence interval for the mean time spent with friends each week.<BR>\n" );
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document.write( "sample mean = 9.2 hrs\r<BR>\n" );
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document.write( "standard error = E = 1.645*6.7/sqrt(1175) = 0.3215<BR>\n" );
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document.write( "90% CI: 9.2-0.3215 < u < 9.2+0.3215<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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