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If x(1), x(2),…..x(n) are n observations...

If `x_(1), x_(2),…..x_(n)` are n observations such that `Sigmax_(i)^(2)=400 and Sigmax_(i)=80` then the least value of n is

A

18

B

12

C

15

D

16

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The correct Answer is:
D
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