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If barx(1), barx(2), barx(3),………barx(n) ...

If `barx_(1), barx_(2), barx_(3),………barx_(n)` are the means of n groups with `n_(1), n_(2), …………,n_(n)` number of observations, respectively, then the mean `barx` of all the groups taken together is given by

A

`sum_(i=1)^(n)n_ibarx_i`

B

`(sum_(i=1)^(n)n_ibarx_i)/(n^2`

C

`(sum_(i=1)^(n)n_ibarx_i)/(sum_(i=1)^(n)n_i)`

D

`(sum_(i=1)^(n)n_ibarx_i)/(2n)`

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The correct Answer is:
C
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MCGROW HILL PUBLICATION-STATISTICS -MULTIPLE CHOICE QUESTIONS
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