statistics college
posted by melba .
find the range standard deviation and variance for following sample data 2,11,81,29,22,59,78,71,21,43,99,12,38,74,56,81

Find the mean first = sum of scores/number of scores
Subtract each of the scores from the mean and square each difference. Find the sum of these squares. Divide that by the number of scores to get variance.
Standard deviation = square root of variance
Range = highest score  lowest
I'll let you do the calculations.