document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1162361>Question 1162361</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Use a normal approximation to find the probability of the indicated number of voters. In this​ case, assume that 127 eligible voters aged​ 18-24 are randomly selected. Suppose a previous study showed that among eligible voters aged​ 18-24, 22% of them voted.<BR>\n" );
document.write( "Probability that fewer than 33 voted </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #786260 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=786260\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The prior mean is np=127*.22=27.94<BR>\n" );
document.write( "sd is sqrt(V) and V=np(1-p)=27.94*.78=21.79<BR>\n" );
document.write( "so sd is 4.67\r<BR>\n" );
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document.write( "fewer than 33, use 32.5 with continuity correction factor<BR>\n" );
document.write( "z<(32.5-27.94)/4.67<BR>\n" );
document.write( "z< 0.98<BR>\n" );
document.write( "probability is 0.8365\r<BR>\n" );
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document.write( "Can use binomial to check the probability 32 or fewer voted, the exact value, which is 0.8360.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );