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If barx1,barx2,barx3,….., barxn are the ...

If `barx_1,barx_2,barx_3,….., barx_n` are the means of n groups with `n_1,n_2,…..n_i` numbers of observation respectively , then the mean `barx` of all the group taken together is given by

A

`underset(i=1)overset(n)sumn_ibarx_i`

B

`(underset(i=1)overeset(n)sumn_ibarx_1)/n^2`

C

`(underset(i=1)overset(n)sumn_ibarx_1)/(underset(i=1)overset(n)sumn_1)`

D

`(underset(i=1)overset(n)sumn_ibarx_1)/(2n)`

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MODERN PUBLICATION-STATISTICS-EXERCISE
  1. The mean of the ungrouped data is given by

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  2. The mean of xi and x2 is M1 and that of x1,x2,x3,x4 is M2. Then the me...

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  3. If M and Mg represents the mean of the raw and grouped data, respectiv...

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  4. The mean of the cubes of the fist n natural number is

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  5. The mean of first 10 natural numbers is

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  6. The average age of a group of eight is same as it was 3 years ago, whe...

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  7. The arithematic mean of 6,10,x and 12 is 8. the value of x is

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  8. The mean age of combined groupd of men and women is 25 years. If the m...

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  9. If barx1,barx2,barx3,….., barxn are the means of n groups with n1,n2,…...

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  10. The mean of x1,x2 is 6 and mean of x1,x2,x3 is 7, find the value of x3

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  11. Find the median of the following data: 12,11,6,7,10,17,9,15,13

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  12. Find the missing frequency k from the following data if mean is 16.​

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  13. For the data 1,5,7,x+1,9,x-2,3 if the mean is 4, find the value of x. ...

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  14. The scores of Mathemtics test 75,69,88,95,88,64,75,95,90,88,44,59,88,6...

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  15. If a football team scored following number of goals in 1 matches, then...

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  16. The points scored by a basket ball team in a seris of matches are as f...

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  17. For what value of x the mode of the following data is 5? 1,2,5,7,5,2,5...

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  18. Find x+y+z

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  19. The mean of the following distribution is 50 find the value of a and ...

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  20. The value of C (47, 4) + underset (r=1) overset (5) sum (52-r,3) is:

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