Find the standard deviation , varience and coefficient of varience 1,2,3,4,5.

Find the standard deviation for the following data:

Find the standard deviation of the first n natural numbers.

Find the mean and standard deviation using short-cut method:

Let x_1,x_2, x_3, x_4, x_5 be the observations with mean m and standard deviation S. The standard deviation of the observations kx_1,kx_2,kx_3,kx_4,kx_5 is ……….

Two sets each of 20 observations , have the same standard deviation 5. The first set has a mean 17 and the second a mean 22. Determine the standard deviation of the set obtained by combining the given two sets.

Find the coefficient of x^5 in (x+3)^8

The mean and standard deviation of a group of 100 observations were found to be 20 and 3, respectively. Later on it was found that three observations were incorrect, which were recorded as 21, 21 and 18. Find the mean and standard deviation if the incorrect observations are omitted.

Coefficient of variation of two distributions are 60 and 70 their standard deviations are 21 and 16, respectively . What are their arithmetic means.

Find the variance and standard deviation for each of the data: 8,9,11,13,14,15,21

Find the variance and standard deviation for the following data :