document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=747346>Question 747346</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Political Survey    A political analyst found that 43% of 300 Republican voters feel that the federal government has too much power.  Find the 95% confidence interval of the population proportion of Republican voters who feel this way.\r<BR>\n" );
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document.write( "A sample of 25 novels has a standard deviation of 9 pages. Find the 95% confidence interval of the population standard deviation.<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 #454860 by </B><A HREF=/tutors/aboutme.mpl?userid=mikeebsc><B>mikeebsc(26)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mikeebsc><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=454860\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I will get to problem 1 if I have time tonight, otherwise I recommend re-posting it alone, and in the future posting each problem separately :)\r<BR>\n" );
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document.write( " Problem 2:<BR>\n" );
document.write( "The formula for a confidence interval is the estimate -+ the margin of error.<BR>\n" );
document.write( "To find the margin of error we use the formula:<BR>\n" );
document.write( "E=Zc(Std. Dev./square root of sample size (Zc=Z critical and there are tables that show the values for 80%, 90%, 95%, and 99% in most textbooks and on the internet)\r<BR>\n" );
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document.write( "For a 95% confidence interval, Zc=1.96  SO:\r<BR>\n" );
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document.write( "E=1.96(9/square root of 25) = 3.528  SO: The confidence interval is:<BR>\n" );
document.write( "(9-3.528),(9+3.528) </SPAN>\n" );
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