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If sum (i=1) ^(9) (x (i) - 5) = 9 and su...

`If sum _(i=1) ^(9) (x _(i) - 5) = 9 and sum_(i =1) ^(9) (x _(i) - 5) ^(2) = 45, ` then the standard deviation of the 9 terms `x _(1), x _(2),....,x _(9)` is

A

3

B

9

C

4

D

2

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The correct Answer is:
D
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