document.write( "Question 1178333: Use the formula and show your work for finding the sample standard deviation and variance of the scores on a test:
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Algebra.Com's Answer #807543 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Make this list:\r\n" );
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document.write( "i  xi\r\n" );
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document.write( "1  65\r\n" );
document.write( "2  88\r\n" );
document.write( "3  83\r\n" );
document.write( "4  80\r\n" );
document.write( "5  78\r\n" );
document.write( "6  90\r\n" );
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document.write( "Find the mean (the average of those 6 number which is 80 2/3\r\n" );
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document.write( "Then you subtract the mean, x̄ = 80 2/3 from each one, and put them in a list\r\n" );
document.write( "out to the right:\r\n" );
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document.write( "i  xi    xi-x̄\r\n" );
document.write( "---------------\r\n" );
document.write( "1  65  -15 2/3\r\n" );
document.write( "2  88    7 1/3\r\n" );
document.write( "3  83    2 1/3\r\n" );
document.write( "4  80   -  2/3  \r\n" );
document.write( "5  78   -2 2/3\r\n" );
document.write( "6  90    9 1/3\r\n" );
document.write( "--------------\r\n" );
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document.write( "Then you square each number in that list and put them in a list out to the\r\n" );
document.write( "right:\r\n" );
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document.write( "i  xi    xi-x̄    (xi-x̄)²\r\n" );
document.write( "------------------------\r\n" );
document.write( "1  65  -15 2/3   245 4/9\r\n" );
document.write( "2  88    7 1/3    53 7/9\r\n" );
document.write( "3  83    2 1/3     5 4/9\r\n" );
document.write( "4  80   -  2/3       4/9\r\n" );
document.write( "5  78   -2 2/3     7 1/9\r\n" );
document.write( "6  90    9 1/3    87 1/9\r\n" );
document.write( "-------------------------\r\n" );
document.write( "  484    0       399 1/3  \r\n" );
document.write( "   ÷              ÷\r\n" );
document.write( "   6              5 <--divide by 1 less than the number of numbers.\r\n" );
document.write( "   =              = \r\n" );
document.write( "80 2/3           79 13/15\r\n" );
document.write( "   =              =\r\n" );
document.write( "   x̄             σ² = the variance of the sample\r\n" );
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document.write( "To get the standard deviation, we take the square root of the variance:\r\n" );
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document.write( "                 \"sigma=sqrt%2879%2613%2F15%29=8.936815242\" <--standard deviation\r\n" );
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document.write( "Edwin
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