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The mean and variance of n observations ...

The mean and variance of n observations `x_(1), x_(2), x_(3),……..,x_(n)` are 5 and 0 respectively. If `sum_(i=1)^(n) x_(i)^(2) = 400`, then the value of n is equal to

A

80

B

25

C

20

D

16

Text Solution

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The correct Answer is:
D
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