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If x(1), x(2),"…......." x(18) are obser...

If `x_(1), x_(2),"…......." x_(18)` are observation such that `sum_(j=1)^(18)(x_(j) -8) = 9` and `sum_(j=1)^(18)(x_(j) -8)^(2) = 45`, then the standard deviation of these observations is

A

`4//9`

B

`9//4`

C

` 3//2`

D

none of these

Text Solution

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The correct Answer is:
C
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