document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1152392>Question 1152392</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In a Gallup poll, 2400 randomly selected adults were surveyed and 39% of them said that they used the internet for shopping at least a few times a year. Find a 95% confidence interval estimate of the percentage of adults who use the internet for shopping. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #774716 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=774716\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 95% half-interval is 1.96*sqrt(p*(1-p)/n)<BR>\n" );
document.write( "this is 1.96*sqrt (.39*.61/2400)<BR>\n" );
document.write( "=0.0195<BR>\n" );
document.write( "so the interval is (0.3705, 0.4095) </SPAN>\n" );
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