document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1113822>Question 1113822</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A study of peach trees found that the average number of peaches per tree was 525. The standard deviation of the population is 105 peaches per tree. A scientist wishes to find the 80% confidence interval for the mean number of peaches per tree. How many trees does she need to sample to obtain an average accurate to within 12 peaches per tree? <BR>\n" );
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document.write( "A) 77\r<BR>\n" );
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document.write( "B)55\r<BR>\n" );
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document.write( "C)83\r<BR>\n" );
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document.write( "D) 126\r<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 #728900 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=728900\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  A study of peach trees found that the average number of peaches per tree was 525. The standard deviation of the population is 105 peaches per tree. A scientist wishes to find the 80% confidence interval for the mean number of peaches per tree. How many trees does she need to sample to obtain an average accurate to within 12 peaches per tree?<BR>\n" );
document.write( "Since ME = z*s/sqrt(n) <BR>\n" );
document.write( "n = [z*s/ME]^2 = [1.2816*105/12]^2<BR>\n" );
document.write( "n = 126 when rounded up<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( "A) 77 <BR>\n" );
document.write( "B)55 <BR>\n" );
document.write( "C)83 <BR>\n" );
document.write( "D) 126  </SPAN>\n" );
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