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You can get a detail definition here https://en.wikipedia.org/wiki/Varianceduongthang wrote:pls, help
what is variance?
Variance in this Example is if mean is mpkw209 wrote:Is the standard deviation of the set of measurements x1, x2, x3....x20 less than 3?
A) The variance for the set of measurements is 4.
B) For each measurement, the difference between the mean and that measurement is 2.
@ajith bhai,ajith wrote:Variance in this Example is if mean is mpkw209 wrote:Is the standard deviation of the set of measurements x1, x2, x3....x20 less than 3?
A) The variance for the set of measurements is 4.
B) For each measurement, the difference between the mean and that measurement is 2.
(m-x1)^2+(m-x2)^2 ......+ (m-x20)^2)/20
Standard deviation is the square root of the variance.
a) Variance =4 ; SD = 2
b) Variance = (2^2+2^2.....+2^2)/20 = 2^2 = 4; SD = 2
A and B are independently sufficient! D
