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प्रश्न
Let x1, x2, ..., xn be n observations and `barx` be their arithmetic mean. The formula for the standard deviation is given by ______.
विकल्प
(x_i - barx)^2`
`(x_i - barx)^2/n`
`sqrt((x_i - barx)^2/n`
`sqrt(x^2/n + barx^2)`
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उत्तर
Let x1, x2, ..., xn be n observations and `barx` be their arithmetic mean. The formula for the standard deviation is given by `sqrt((x_i - barx)^2/n`.
Explanation:
The formula for S.D. = `sigma`
= `sqrt((sum(x_i - barx)^2)/n`
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