document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1052857>Question 1052857</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can you please help with this?\r<BR>\n" );
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document.write( "An insurance company checks police records on 600 randomly selected auto accidents and notes that teenagers were at the wheel in 90 of them. Construct a 95% confidence interval estimate of the proportion of auto accidents that involve teenage drivers.\r<BR>\n" );
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document.write( "Thank you very much for any help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #668151 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=668151\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The point estimate is 90/600=0.15<BR>\n" );
document.write( "The standard error is sqrt(p*(1-p))/n)<BR>\n" );
document.write( "sqrt(0.15*-0.85)/600<BR>\n" );
document.write( "=sqrt(0.0002125)<BR>\n" );
document.write( "=0.0146<BR>\n" );
document.write( "95% CI is p hat +/- 1.96*SE<BR>\n" );
document.write( "the interval is +/-0.0286<BR>\n" );
document.write( "The 95%CI for the true proportion is (0.121,0.179) </SPAN>\n" );
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