document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=315101>Question 315101</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In a Gallup poll, 1025 randomly selected adults were surveyed and 29% of them said that they used the Internet for shopping at least a few times a year.<BR>\n" );
document.write( "Find the margin of error.<BR>\n" );
document.write( "Find a 99% 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 #225633 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=225633\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In a Gallup poll, 1025 randomly selected adults were surveyed and 29% of them said that they used the Internet for shopping at least a few times a year.<BR>\n" );
document.write( "Find the margin of error.<BR>\n" );
document.write( "Find a 99% confidence interval estimate of the percentage of adults who use the Internet for shopping.<BR>\n" );
document.write( "--------------------------<BR>\n" );
document.write( "sample proportion: 0.29<BR>\n" );
document.write( "---<BR>\n" );
document.write( "ME = (invT(0.995 with df = 1024)sqrt[0.29*0.71/1025] = 2.5806*0.0142 = 0.0366<BR>\n" );
document.write( "---<BR>\n" );
document.write( "99% CI: 0.29-0.0366 < p < 0.29+0.0366<BR>\n" );
document.write( "==============================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );