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A box contains 6 pens , 2 of which ...

A box contains 6 pens , 2 of which are defective Two pens are taken randomly
from the bax . If r,v. X. : Number of defective pens obtained ,
then standard deviation of `x= `

A

(a) `+- 4/(3sqrt(5))`

B

(b) `8/3`

C

(c) `16/45`

D

(d) ` 4/(3sqrt(5))`

Text Solution

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The correct Answer is:
D
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