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The number of observations of two sample...

The number of observations of two samples are 30 and 40 respectively, each have same mean value 61, but variance are 25 and 16 respectively. Find S.D. of final sample of 70 observations mixed by above two samples.

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PATHFINDER-STATISTICS-QUESTION BANK
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  2. Calculate the mean and standard deviation of the numbers-natural numbe...

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  5. Find the mean deviation about the mean of the data : 7, 8, 4, 13, 9, 5...

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  6. Find the mean deviation about the mean of the data : 7, 8, 4, 13, 9, 5...

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  7. Find the SD of first 10 multiples of 3.

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  8. The mean and variance of seven observations are 8 and 16 respectively....

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  9. The mean and variance of seven observations are 8 and 16 respectively....

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  10. The mean and standard deviation of 100 observations were calculated as...

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  12. Let x1,x2,x3,…xn be n values of a variable x. If these values are chan...

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  13. The mean of 5 observation is 4.4 and their variance is 8.24. If three ...

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  14. Find the mean deviation about the mean of the data : 7, 8, 4, 13, 9, 5...

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  15. Find the mean diaviation with respect to median of the frequency dist...

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  16. Find the mean diaviation with respect to median of the frequency dist...

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  17. Calculate the mean and standard deviation of the numbers-natural numbe...

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  18. The mean and variance of 8 observations are 9 and 9.25 respectively. I...

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  19. For a group of 200 candidates the mean and S.D. were found to be 40 an...

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  20. The number of observations of two samples are 30 and 40 respectively, ...

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