document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1157147>Question 1157147</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Two samples are taken with the following numbers of successes and sample sizes<BR>\n" );
document.write( "r1 = 29 <BR>\n" );
document.write( "r2 = 31<BR>\n" );
document.write( "n1 = 63 <BR>\n" );
document.write( "n2 = 77\r<BR>\n" );
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document.write( "Find a 98% confidence interval, round answers to the nearest thousandth.<BR>\n" );
document.write( "_______ < p1−p2 < _______ <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 #780017 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=780017\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This is ready made to be put into a calculator.<BR>\n" );
document.write( "(-.14, +.25) is the 98% CI.\r<BR>\n" );
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document.write( "By hand, the half-interval or z*SE  is z(0.99)*sqrt (p1(1-p1)/n1)+(p2(1-p2)/n2))<BR>\n" );
document.write( "=2.33*sqrt(0.00706)<BR>\n" );
document.write( "and to rounding error, you get a half-interval of 0.195, which is half the difference between -.14 and +.25 above.\r<BR>\n" );
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