Cumulative Standards Review
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How can we find the standard deviation of a data set?
C
Standard Deviation |
The standard deviation of a data set is the average amount by which each individual value deviates or differs from the mean.
σ=n(x1−μ)2+(x2−μ)2+⋯+(xn−μ)2
In the above formula, x1,…,xn are the values of the set of data, μ is the mean, and n is the number of values.
|
xn | xn−μ | (xn−μ)2 |
---|---|---|
8 | 8−11.67=-3.67 | (-3.67)2=13.4689 |
11 | 11−11.67=-0.67 | (-0.67)2=0.4489 |
14 | 14−11.67=2.33 | 2.332=5.4289 |
7 | 7−11.67=-4.67 | (-4.67)2=21.8089 |
12 | 12−11.67=0.33 | 0.332=0.1089 |
18 | 18−11.67=6.33 | 6.332=40.0689 |
Sum of Values | 81.3334 |