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The standard deviations of two sets cont...

The standard deviations of two sets containing 10 and 20 members are 2 and 3 respectively measured from their common mean 5. Find the S.D. for the whole set of 30 members.

A

`(2)/(sqrt(3))`

B

`sqrt(6)`

C

`sqrt(((22)/(3)))`

D

`sqrt(3)`

Text Solution

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The correct Answer is:
C
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