document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1029764>Question 1029764</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am helping my daughter in math and she need help with a qustion where she needs to find the range, variance, and the standard deviation for the sets of data.<BR>\n" );
document.write( "A) The ages of people at a family reunion.<BR>\n" );
document.write( "2,3,7,10,16,17,39,42,44,45,49,50,51,56,70, 77<BR>\n" );
document.write( "B) Number of tracks in CDs <BR>\n" );
document.write( "8,10,11,11,11,12,13,13,14,15,16 <BR>\n" );
document.write( "I myself have no idea how to help her and she does not have a text book for me too look off of any hlep is appreciated. \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 #644712 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=644712\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 2,3,7,10,16,17,39,42,44,45,49,50,51,56,70, 77<BR>\n" );
document.write( "Easier to use a calculator for these, but range is the easiest: high minus low or 75<BR>\n" );
document.write( "variance is the squared difference between each value and the mean divided by  where n is the number of observations, or 16<BR>\n" );
document.write( "The standard deviation is the square root of the variance.<BR>\n" );
document.write( "on a TI-83, use STAT then LIST, enter the numbers then STAT then CALC, and do 1-variable stats<BR>\n" );
document.write( "what you need is <BR>\n" );
document.write( "variance: which it doesn't give you.  BUT, you have sigma, the o-shaped thing at the bottom of the list, which is the standard deviation:  it is 23.103.  That is enough decimal places.<BR>\n" );
document.write( "The variance is the square of that or 533.73<BR>\n" );
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document.write( "number of tracks in CDs.<BR>\n" );
document.write( "standard deviation is 2.208<BR>\n" );
document.write( "variance is 4.876<BR>\n" );
document.write( "range is 8.<BR>\n" );
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document.write( "Doing by hand is tedious except for mean.<BR>\n" );
document.write( "You have to take the difference of each from mean, square it and add all the squared differences.<BR>\n" );
document.write( "With sample data, we typically divide by n-1 or 1 less than the number of observations.  With populations, we divide by the number. Write on the paper you treated this as a population.  If there is an issue, google variance and you will see that as the primary definition.  \r<BR>\n" );
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