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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

`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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MBD-STATISTICS-EXERCISE
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  2. The class marks of a frequency distribution are given as follows : 15,...

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  3. In the class intervals 10-20, 20-30, the number 20 is included in.

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  4. A grouped frequency table with class intervals of equal sizes using 25...

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  5. A grouped frequency distribution table with classes of equal sizes usi...

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  6. To draw a histogram to represent the following frequency ditribution :...

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  7. The mean of five numbers is 30. If one number is excluded, their mean ...

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  8. If the mean of the observations : x, x + 3, x + 5, x + 7, x + 10 is 9,...

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  9. If barx represents the mean of n observations x1, x2,…….,xn , then val...

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  10. If each observation of the data is increased by 5, then their mean

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  11. Let barx be the mean of x1,x2,……,xn and bary the mean of y1,y2……,yn ba...

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  12. If barx is the mean of x1,x2,x3, ………..xn , then for ane0, the mean of ...

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

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  14. The mean of 100 observations is 50. If one of the observations which w...

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  15. There are 50 numbers. Each number is subtracted from 53 and the mean o...

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  16. The mean of 25 observations is 36. Out of these observationsif the mea...

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  17. The median of the data 78, 56, 22, 34, 45, 54, 39, 68, 54, 84 is

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  18. For drawing a frequency polygon of a continuous frequency distribution...

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  19. Median of the following numbers : 4, 4, 5, 7, 6, 7, 7, 12, 3 is

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  20. Mode of the data 15, 14, 19, 20, 14, 15, 1 6, 14, 15, 18, 14, 19, 15, ...

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