document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1119719>Question 1119719</A>: <I><SPAN STYLE=\"word-break: break-all;\">  Insurance companies are interested in knowing the population percent of drivers who always buckle up before riding in a car. They randomly survey 403 drivers and find that 284 claim to always buckle up. Construct a Invalid variable% confidence interval for the population proportion that claim to always buckle up.\r<BR>\n" );
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document.write( "Enter your answer using interval notation. Example: [2.1,5.6172)  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #735412 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=735412\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> proportion point estimate is 284/403=0.7047=p hat<BR>\n" );
document.write( "interval for 95% CI uses 1.96*sqrt(ph*(1-ph)/n)<BR>\n" );
document.write( "this interval is 0.0445<BR>\n" );
document.write( "CI is 0.7047 +/- 0.0445<BR>\n" );
document.write( "(0.6602, 0.7492) </SPAN>\n" );
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