## anonymous 5 years ago How do you find the range, variance, and standard deviation of a set of data?

1. anonymous

The range of a set is the largest value of the set minus the smallest value of the set. The variance: Make N the mean of the set, the variance is then (X0 + N)^2 + (X1 + N)^2 + ... (Xn + N)^2

2. anonymous

so the rage should be one number, correct?

3. anonymous

Standard deviation is the square root of the variance.

4. anonymous

Suppose we have set of reals S = {0, 2, 75, -2} The range is 75 --2 = 77

5. dumbcow

Range is max value - min value $Variance = \frac{\sum_{}^{}(X - x_{i})^{2}}{n-1}$

6. anonymous

Thanks! I'm still confused with variance

7. anonymous

Suppose we have set of reals S = {0, 2, 75, -2} The mean is S is (0 + 2 + 75 - 2) / 4 = 18.75 The variance is ((0 + 18.75)^2 + (2 + 18.75)^2 + (75 + 18.75)^2 + (18.75 - 2)^2) / (4 - 1)