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The standard deviation of n observations...

The standard deviation of n observations `x_(1), x_(2), …, x_(n)` is 2. If `sum_(i=1)^(n)x_(i)=20 and sum_(i=1)^(n)x_(i)""^(2)=100`, then n is :
a) 10 or 20 b) 5 or 10 c)5 or 20 d) 5 or 15

A

10 or 20

B

5 or 10

C

5 or 20

D

5 or 15

Text Solution

Verified by Experts

The correct Answer is:
C
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