document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1141613>Question 1141613</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An automotive manufacturer wants to know the proportion of new car buyers who prefer foreign cars over domestic.  In an earlier study, the population proportion was estimated to be 0.33.\r<BR>\n" );
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document.write( "How large a sample would be required in order to estimate the fraction of new car buyers who prefer foreign cars at the 95% confidence level with an error of at most 0.02? Round your answer up to the next integer.<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 #762193 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=762193\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the half-interval is z(0.975)sqrt (p*(1-p)/n)<BR>\n" );
document.write( "0.02=1.96*sqrt(0.33*0.67/n)<BR>\n" );
document.write( "square both sides and move n over<BR>\n" );
document.write( "0.0004n=3.84*0.33*0.67<BR>\n" );
document.write( "n=2122.56<BR>\n" );
document.write( "round up to 2123 </SPAN>\n" );
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