document.write( "Question 224587: A class of 15 kindergarteners had the following weights in pounds:
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Algebra.Com's Answer #167787 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "A class of 15 kindergarteners had the following weights in pounds:\r\n" );
document.write( "53    39    46    36    39    52    49    52    \r\n" );
document.write( "46    47    48    51    48    51    41\r\n" );
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document.write( "Find the mean, variance, and standard deviation.\r\n" );
document.write( "  (Points: 5)\r\n" );
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document.write( "List them in a column with heading X, add them and divide by the\r\n" );
document.write( "number of numbers, which is 15.  That is the mean:\r\n" );
document.write( "        X\r\n" );
document.write( "       53    \r\n" );
document.write( "       39    \r\n" );
document.write( "       46    \r\n" );
document.write( "       36    \r\n" );
document.write( "       39    \r\n" );
document.write( "       52    \r\n" );
document.write( "       49    \r\n" );
document.write( "       52    \r\n" );
document.write( "       46    \r\n" );
document.write( "       47    \r\n" );
document.write( "       48    \r\n" );
document.write( "       51    \r\n" );
document.write( "       48    \r\n" );
document.write( "       51    \r\n" );
document.write( "       41\r\n" );
document.write( "      ---\r\n" );
document.write( "   15)698\r\n" );
document.write( "_     ---  \r\n" );
document.write( "X = 46.5333···\r\n" );
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document.write( "Subtract that mean from each of the numbers and place in\r\n" );
document.write( "another column headed with X-X\r\n" );
document.write( "                 _\r\n" );
document.write( "        X      X-X\r\n" );
document.write( "       53   -6.4666...  \r\n" );
document.write( "       39   -7.5333... \r\n" );
document.write( "       46   -0,5333... \r\n" );
document.write( "       36  -10.5333... \r\n" );
document.write( "       39   -7.5333...  \r\n" );
document.write( "       52    5.4666... \r\n" );
document.write( "       49    2.4666...\r\n" );
document.write( "       52    5.4666...\r\n" );
document.write( "       46   -0.5333... \r\n" );
document.write( "       47    0.4666...\r\n" );
document.write( "       48    1.4666...\r\n" );
document.write( "       51    4.4666...\r\n" );
document.write( "       48    1.4667...\r\n" );
document.write( "       51    4.4666...\r\n" );
document.write( "       41   -5.5333...\r\n" );
document.write( "      ---\r\n" );
document.write( "   15)698\r\n" );
document.write( "_     ---  \r\n" );
document.write( "X = 46.5333···\r\n" );
document.write( "           _\r\n" );
document.write( "The mean = X = 46.5333...\r\n" );
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document.write( "Now square all those in that list and place them\r\n" );
document.write( "                            _\r\n" );
document.write( "in a third column headed (X-X)², add that column and\r\n" );
document.write( "divide by one less than 15, or 14\r\n" );
document.write( "                 _             _ \r\n" );
document.write( "        X      X-X          (X-X)²   \r\n" );
document.write( "       53   -6.4666...    41.81777...\r\n" );
document.write( "       39   -7.5333...    56.75111...\r\n" );
document.write( "       46   -0.5333...      .28444...\r\n" );
document.write( "       36  -10.5333...   110.95111...\r\n" );
document.write( "       39   -7.5333...    56.75111... \r\n" );
document.write( "       52    5.4666...    29.88444...\r\n" );
document.write( "       49    2.4666...     6.08444... \r\n" );
document.write( "       52    5.4666...    29.88444...\r\n" );
document.write( "       46   -0.5333...     0.28444...\r\n" );
document.write( "       47    0.4666...     0.21777...\r\n" );
document.write( "       48    1.4666...     2.15111... \r\n" );
document.write( "       51    4.4666...    19.95111... \r\n" );
document.write( "       48    1.4667...     2.15111...\r\n" );
document.write( "       51    4.4666...    19.95111...\r\n" );
document.write( "       41   -5.5333...    30.61777...\r\n" );
document.write( "      ---                ------------\r\n" );
document.write( "   15)698             14)407.73333...\r\n" );
document.write( "_     ---                ------------\r\n" );
document.write( "X = 46.5333···         s²=29.12380952...\r\n" );
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document.write( "s² is the variance = 29.12380952...\r\n" );
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document.write( "s is the standard deviation = \"sqrt%2829.12380952%29=5.396647989\"...\r\n" );
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document.write( "Edwin
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