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The mean and standard deviation of 20 ob...

The mean and standard deviation of 20 observations are found to be 10 and 2, respectively. One rechecking, it was found that an observation 8 was incorrect. Calculate the correct mean and standard deviation in each of the following cases. (i)      If wrong item is omitted (ii)     If it is replaced by 12.

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RD SHARMA ENGLISH-STATISTICS-All Questions
  1. The mean and variance of 7 observation is 8 and 16. If five of the obs...

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  2. If for a sample of size 60, we have the following information sumxi^2=...

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  3. The mean and standard deviation of 20 observations are found to be ...

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  4. Consider the numbers 1,2,3,4,5,6,7,8,9,10. If 1 is added to each num...

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  5. If for distribution of 18 observations sum(xi-5)=3a n dsum(xi-5)^2=43 ...

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  6. If the men and standards deviation of 100 observations are 50 and 4 ...

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  7. Let x1,\ x2,\....,\ xn values of variable X and let 'a' be non zero re...

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  8. If two variates X a n d Y are connected by the relation Y=(a X+b)/c ,w...

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  9. Let x1, x2, x3, , be n values of a variable X. If these values are ch...

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  10. If for a sample of size 60, we have the following information sumxi^2=...

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  11. The weight of coffee in 70 jars is shown in the following table: Weigh...

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  12. Suppose that samples of polythene bags from two manufacturers, A and B...

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  13. Let x1, x2, ...... ,xn be values taken by a variable Xa n dy1, y2,......

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  14. The sum of the squares of deviation of 10 observations from their mean...

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  15. If the S.D. of a set of observations is 8 and if each observation is ...

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  16. Find the mean and variance of frequency distribution given below: xi :...

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  17. The mean deviation of the series a , a+d , a+2d , , a+2n from its mea...

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  18. The standard deviation of the data: x : , 1, a , a^2 , ..., a^n f: , ...

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  19. The mean deviation of the numbers 3,4,5,6,7 from the mean is(a) 25  ...

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  20. A batsman scores run in 10 innings as 38,70,48,34,42,55,63,46,54 and ...

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