The mean of the values of `1,2,3,...n` with respectively frequencies `x, 2x, 3x,...,nx` is:

If the variate of a distribution takes the values 1^(2), 2^(2), 3^(2),….n^(2) with frequencies n, n-1, n-2,….3,2,1 respectively, then the mean value of the distribution is

If the variate of a distribution takes the values 1^(2), 2^(2), 3^(2),….n^(2) with frequencies n, n-1, n-2,….3,2,1 respectively, then the mean value of the distribution is

If the mean of observations x_1.x_2,x_3…..x_n is barx then the mean of x_1+a,x_2+a,…...x_n+a will be

The mean of x_1,x_2 is 6 and mean of x_1,x_2,x_3 is 7, find the value of x_3

The means and variance of n observation x_1, x_2, x_3,....x_n are 5 and 0 respectively . If sum_(i=1)^(n) x_(i)^(2) = 400 , then find the value of n

Period of sin(x+2x+3x+....+nx) is

Suppose the values x_1, x_2,…..x_n having frequency f_1, f_2…...f_n respectively have mean value overset- x and variation sigma^2 .Let a be a fixed real number. Show that the values x_1+a,x_2+a,….,x_n+a with frequency f_1,f_2….f_n respectively will have mean value overset-x+a and variance sigma

The numbers 3, 5, 6 and 4 have frequencies of x, x + 2, x -8 and x+ 6, respectively। If their mean is 4 then the value of x is