Question
Download Solution PDFCalculate the standard deviation if the mean of a certain set of observations is 20 and the mean of the squares of the same observations is 500.
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFGiven
Mean of certain number = 20
Mean of square of same observation = 500
Formula used
σ = √[(∑x2/n –(∑x/n)2]
(∑x/n) = mean
∑x2/n = mean of square
Calculation
Standard deviation is given by
⇒ √[(∑(x2/n –(∑x/n)2] = √[500 – (20)2]
⇒ √(500 – 400)
∴ Standard deviation is 10
Last updated on Jul 17, 2025
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