1. If the varience of the data is 121 then the standard deviation of the data is

2. If the mean of the following data is 20.6, then the value of p is
x = 10 15 p 25 35
f = 3 10 25 7 5

3. If the mean of first n natural numbers is 5n/9, then n =

4. If one of the observation is zero then geometric mean is

5. Which one is measure of dispersion method

6. If a variable takes discrete values x + 4, x – 7/2, x – 5/2, x – 3, x – 2, x + 1/2, x – 1/2, x + 5 (x > 0), then the median is

7. If covariance between two variables is 0, then the correlation coefficient between them is

8. The mean of a group of 100 observations was found to be 20. Later on, it was found that three observations were incorrect, which was recorded as 21, 21 and 18. Then the mean if the incorrect observations are omitted is

9. Varience is independent of change of

10. Let x₁, x₂, x₃, ……… , x_n, be n observations and X be the arithmetic mean. Then formula for the standard deviation is given by