document.write( "Question 1158372: Find the range, standard deviation, and variance of
\n" ); document.write( "A survey of 10 fast-food restaurant noted the number of calories in a mid-sized hamburger. The following are results
\n" ); document.write( "514 507 502 498 496 506 458 478 463 514
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Algebra.Com's Answer #854591 by KMST(5396)\"\" \"About 
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Range, standard deviation, and variance are measures of the dispersion of the data in a set.
\n" ); document.write( "A long time ago, in college, I would calculate them using paper and pen, based on their definitions.
\n" ); document.write( "Nowadays, a calculator, or computer software can calculate them for us easily, but we have to understand what this measure tell us and exactly what our devices.
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\n" ); document.write( "Range:
\n" ); document.write( "The range is the difference between the smallest and greatest values.
\n" ); document.write( "\"Range=514-458=highlight%2856%29\"
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\n" ); document.write( "Variance:
\n" ); document.write( "The mean (average) of all 10 values is
\n" ); document.write( "\"%28514%2B507%2B502%2B498%2B496%2B506%2B458%2B478%2B463%2B514%29%2F10=4936%2F10=493.6\"
\n" ); document.write( "The deviations from the mean for the individual values are:
\n" ); document.write( "\"514-493.6=20.4\" (514 appears twice)
\n" ); document.write( "\"507-493.6=13.4\"
\n" ); document.write( "\"502-493.6=8.4\"
\n" ); document.write( "\"498-493.6=4.4\"
\n" ); document.write( "\"496-493.6=2.4\"
\n" ); document.write( "\"506-493.6=12.4\"
\n" ); document.write( "\"458-493.6=-35.6%7D%7D%0D%0A%7B%7B%7B478-493.6=-15.6\"
\n" ); document.write( "\"463-493.6=-30.6\"
\n" ); document.write( "Their squares are:
\n" ); document.write( "\"20.4%5E2=416.16\" (514 appears twice)
\n" ); document.write( "\"13.4%5E2=179.56\"
\n" ); document.write( "\"8.4%5E2=70.56\"
\n" ); document.write( "\"4.4%5E2=19.36\"
\n" ); document.write( "\"2.4%5E2=5.76\"
\n" ); document.write( "\"12.4%5E2=153.76\"
\n" ); document.write( "\"-35.6%5E2=1267.36%7D%7D%0D%0A%7B%7B%7B-15.6%5E2=243.36\"
\n" ); document.write( "\"-30.6%5E2=936.36\"
\n" ); document.write( "The variance is the average of those squares:
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\n" ); document.write( "Standard deviation:
\n" ); document.write( "The standard deviation, as asked in this question, is the square root of the variance as calculated above:
\n" ); document.write( "\"sqrt%28370.84%29=highlight%2819.26%29\" (rounded)
\n" ); document.write( "Software that calculates statistics would have to forms of standard deviation:
\n" ); document.write( "the standard deviation of a population, calculated as above, and
\n" ); document.write( "the standard deviation of a sample, used to estimate the dispersion of the whole population of data based on a sample of N items. In the second case, the sum of squares in divided by N-1 instead.
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