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Question
Standard deviations for first 10 natural numbers is ______.
Options
5.5
3.87
2.97
2.87
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Solution
Standard deviations for first 10 natural numbers is 2.87.
Explanation:
We know that S.D. of first n natural numbers `sqrt((n^2 - 1)/12)`
Here n = 10
∴ S.D. = `sqrt((10)^2 - 1)/12`
= `sqrt(99/12)`
= `sqrt(8.25)`
= 2.87
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