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A series are 2n observations. The half o...

A series are 2n observations. The half of them is a and the reamaining half is -a . If their standard deviation is 2 then |a| = ………

A

2

B

`sqrt2`

C

`1/n`

D

`(sqrt2)/(n)`

Text Solution

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The correct Answer is:
A
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KUMAR PRAKASHAN-STATISTICS-TEXTBOOK BASED MCQS
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  2. In a class, the mean marks of boys is 50 and the mean marks of girls i...

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  3. The variance of 15 observations is 8. If each observation is multiplie...

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  4. The standard deviation for the following data is n = 10 , sum x = ...

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  5. Mean and standard deviation of 100 items are 50 and 4, respectively . ...

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  6. While combined both groups new standard deviation is

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  7. If the standard deviation of variable x is 4 and y = (3x + 7)/(4) then...

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  8. The variance of observations 3,4,5,8 is

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  9. The following data is for 15 observation obtained in an experiment. s...

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  10. The mean deviation about mean of the observation 3, 10, 10, 4, 7, 10, ...

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  11. Following are the marks obtained by 9 students in a mathematics test :...

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  12. A series are 2n observations. The half of them is a and the reamaining...

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  13. Median of nine observations is 20.45 . If 2 is added in last four obse...

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  14. x1,x2, x3,………., xn are n observations . sum(i=1)^(n) (xi - 2) = 100 "...

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  15. The standard deviation of four consecutive numbers in A.P. is sqrt5 . ...

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  16. Variance of first n natural number is …………

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  17. Range of the observations 2,3,5,9,8,7,6,5,7,4,3, is ………

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  18. mean of the series a , a+d, a+2d,……………, a + 2nd is …..

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  19. Which is not the measur of central tendency ?

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