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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
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  8. If n=10 , X =12a n d∑x ^2 =1530 , then the coefficient of variation...

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  9. The mean deviation for n observations x1, x2, ......... , xn from thei...

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  10. The standard deviation of the observations 6,5,9,13,12,8,10 is (a)6 (...

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  11. If the standard deviation of a variable X \ is \ sigma , then standard...

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  16. The standard deviation of first 10 natural numbers is (a) 8.25        ...

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  17. Let x1, x2, ,xn be xn observations. Let yi=a xi+b for i=1,2,...,n wher...

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  18. Let x1, x2, ... ,xn be n observations and barX be their arithmetic me...

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  19. The following are some particulars of the distribution of weights of ...

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