document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1186970>Question 1186970</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In a random sample of 380 residents of Fiction County, it was found that only 57 could correctly name the president of France. Use this information to construct a 90% confidence interval for p, the proportion of all residents of Fiction County who can correctly name the President of France.\r<BR>\n" );
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document.write( "Round your answers to three significant figures.\r<BR>\n" );
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document.write( "Answer: We are 90% confident that __ < p < __ .<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 #820459 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=820459\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> p hat=57/380=0.15<BR>\n" );
document.write( "90% half-interval is z(.95)*sqrt(.15*.85/380)<BR>\n" );
document.write( "=1.645*0.0183<BR>\n" );
document.write( "=0.0301<BR>\n" );
document.write( "the interval is (0.120, 0.180) </SPAN>\n" );
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