document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=125696>Question 125696</A>: <I><SPAN STYLE=\"word-break: break-all;\"> looking for the standard deviation for these numbers.\r<BR>\n" );
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document.write( "38  45  47  47  48  50  50  52  58  62<BR>\n" );
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document.write( "62  63  64  68  70  72  72  72  72  74<BR>\n" );
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document.write( "78  79  80  80  82  84  88  90  94  99\r<BR>\n" );
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document.write( "First I add all numbers to find the mean.  2040/30=68<BR>\n" );
document.write( "here is where I get lost. \r<BR>\n" );
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document.write( "I subtract the lowest number from the mean. 38-68=-30<BR>\n" );
document.write( "and subtract the largest number from the mean. 99-68=31<BR>\n" );
document.write( "I square them and add them together and that is where I get stuck.\r<BR>\n" );
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document.write( "(-30*-30)=900 (31*31)=961.  900+961=1861 Now am I supposed to divide by 2 or 30\r<BR>\n" );
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document.write( "I am a little confused.\r<BR>\n" );
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document.write( "Darrin </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #92079 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=92079\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You need to subtract the mean from EACH of the 30 data points.<BR>\n" );
document.write( "Then square EACH of the differences.<BR>\n" );
document.write( "Then add up all of the squared differences.<BR>\n" );
document.write( "Divide this sum of squares by the number of data points minus 1 (29) (this is because you are doing a sample of a population).<BR>\n" );
document.write( "Take the square root of the quotient.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sigma=sqrt%28%281%2F%28N-1%29%29%2Asum%28%28x%5Bi%5D-x%5Bbar%5D%29%5E2%2Ci=1%2CN%29%29 ALIGN=MIDDLE  ALT=\"sigma=sqrt%28%281%2F%28N-1%29%29%2Asum%28%28x%5Bi%5D-x%5Bbar%5D%29%5E2%2Ci=1%2CN%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5Bbar%5D ALIGN=MIDDLE  ALT=\"x%5Bbar%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the mean of your sample.\r<BR>\n" );
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document.write( "Drop me a line and I'll send you a spreadsheet that shows all of the calculations. </SPAN>\n" );
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