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The mean and standard deviation of 20 it...

The mean and standard deviation of 20 items is found to be 10 and 2 respectively. At the time of checking it was found that one item 8 was incorrect. If it is replaced by 12, then find the mean and variance.

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The correct Answer is:
10.2 and 3.96
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AAKASH SERIES-STATISTICS -EXERCISE-5.2
  1. Find the variance for the discrete data given below . (i) 6,7,10,12,...

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  2. Find the variance for the discrete data given below. 350, 361, 370, ...

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  3. Find the variance and standard deviation of the following data 5,12 ,...

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  4. If standard deviation of 1, 2, 3, 4, ...,10 is sigma then, show that s...

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  5. If n=10 , sum(i=1)^(10) x(i)=60 and sum(i=1)^(10) x(i)^(2)=1000 then f...

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  6. Calculate the variance and standard deviation of the following continu...

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  7. Calculate the variance and standard deviation of the following continu...

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  8. If the s.d of-5, -4,-3, -2,-1, 0, 1, 2, 3, 4, 5 is sqrt(10) then find ...

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  9. If a variable takes the values 0, 1, 2,…,n with frequencies proporiotn...

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  10. Suppose a population A has 100 observations 101, 102, ...., 200, and a...

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  11. In a series of 2n observations, half of them equals to a and remaining...

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  12. The standard deviations of two sets containing 10 and 20 members are 2...

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  13. If sum(i=1)^(18)(x(i)-8)=9 and sum(i=1)^(18)(x(i)-8)^(2)=45 then find ...

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  14. The mean and standard deviation of 20 items is found to be 10 and 2 re...

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  15. For two data sets each of size 5 the variances are given by 4 and 5 an...

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  16. The means and variance of n observation x1, x2, x3,....xn are 5 and 0 ...

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  17. The standard deviation of n observation x1 , x2, x3 .....,xn is 2. If...

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

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