document.write( "Question 165394: Find the standard deviation. 44, 90, 73, 65, 76, 22, 50, 45, 37 \n" ); document.write( "
Algebra.Com's Answer #121893 by Edwin McCravy(20081)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "List them in a column headed x\r\n" );
document.write( "Draw a line and add the column\r\n" );
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document.write( "    x\r\n" );
document.write( "   44 \r\n" );
document.write( "   90 \r\n" );
document.write( "   73 \r\n" );
document.write( "   65\r\n" );
document.write( "   76\r\n" );
document.write( "   22 \r\n" );
document.write( "   50 \r\n" );
document.write( "   45\r\n" );
document.write( "   37\r\n" );
document.write( "-----\r\n" );
document.write( "  502\r\n" );
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document.write( "Divide the 502 by 9, the number of numbers\r\n" );
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document.write( "    x\r\n" );
document.write( "   44 \r\n" );
document.write( "   90 \r\n" );
document.write( "   73 \r\n" );
document.write( "   65\r\n" );
document.write( "   76\r\n" );
document.write( "   22 \r\n" );
document.write( "   50 \r\n" );
document.write( "   45\r\n" );
document.write( "   37\r\n" );
document.write( "-----\r\n" );
document.write( "9)502\r\n" );
document.write( " ----\r\n" );
document.write( "   55.777···\r\n" );
document.write( "                  _\r\n" );
document.write( "That is the mean, x.  Subtract it from every value,\r\n" );
document.write( "and place it in a column just to the right:\r\n" );
document.write( "             _ \r\n" );
document.write( "    x      x-x\r\n" );
document.write( "   44   -11.77···\r\n" );
document.write( "   90    34.22···\r\n" );
document.write( "   73    17.22···\r\n" );
document.write( "   65     9.22···\r\n" );
document.write( "   76    20.22···\r\n" );
document.write( "   22   -33.77··· \r\n" );
document.write( "   50    -5.77··· \r\n" );
document.write( "   45   -10.77···\r\n" );
document.write( "   37   -18.77···\r\n" );
document.write( "-------------------\r\n" );
document.write( "9)502\r\n" );
document.write( " ----\r\n" );
document.write( "   55.777···\r\n" );
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document.write( "Square every term in that column, and\r\n" );
document.write( "place those in a column to the right,\r\n" );
document.write( "and add them:\r\n" );
document.write( "             _         _ \r\n" );
document.write( "    x      x-x      (x-x)²\r\n" );
document.write( "   44   -11.77···   138.716 \r\n" );
document.write( "   90    34.22···  1171.160 \r\n" );
document.write( "   73    17.22···   296.605\r\n" );
document.write( "   65     9.22···    85.049\r\n" );
document.write( "   76    20.22···   408.938\r\n" );
document.write( "   22   -33.77···  1140.938 \r\n" );
document.write( "   50    -5.77···    33.383\r\n" );
document.write( "   45   -10.77···   116.160\r\n" );
document.write( "   37   -18.77···   352.605\r\n" );
document.write( "---------------------------\r\n" );
document.write( "9)502              3743.554 \r\n" );
document.write( " ----\r\n" );
document.write( "   55.777···\r\n" );
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document.write( "Divide that by 1 less than 9, or 8\r\n" );
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document.write( "             467.944\r\n" );
document.write( "           ---------\r\n" );
document.write( "          8)3743.554\r\n" );
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document.write( "Take the square root of 467.944\r\n" );
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document.write( "       \"sqrt%28467.944%29=21.632\"\r\n" );
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document.write( "The standard deviation, s, is 21.632.\r\n" );
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document.write( "Edwin
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