The standard deviation of n observations`x_(1), x_(2), x_(3),…x_(n)` is 2. If `sum_(i=1)^(n) x_(i)^(2) = 100` and `sum_(i=1)^(n) x_(i) = 20` show the values of n are 5 or 20

If n= 10, sum_(i=1)^(10) x_(i) = 60 and sum_(i=1)^(10) x_(i)^(2) = 1000 then find s.d.

The means and variance of n observations x_(1),x_(2),x_(3),…x_(n) are 0 and 5 respectively. If sum_(i=1)^(n) x_(i)^(2) = 400 , then find the value of n

A data consists of n observations : x_(1), x_(2),……, x_(n) . If Sigma_(i=1)^(n)(x_(i)+1)^(2)=11n and Sigma_(i=1)^(n)(x_(i)-1)^(2)=7n , then the variance of this data is

A data consists of n observations x_(1), x_(2), ..., x_(n). If Sigma_(i=1)^(n) (x_(i) + 1)^(2) = 9n and Sigma_(i=1)^(n) (x_(i) - 1)^(2) = 5n , then the standard deviation of this data is

sum_(i=1)^(n) sum_(i=1)^(n) i is equal to

Let x_(1), x_(2),…,x_(n) be n observations such that sum x_(i)^(2) = 400 and sum x_(i) = 80 . Then a possible value of n among the following is

If barx is the mean of n observations x_(1),x_(2),x_(3)……x_(n) , then the value of sum_(i=1)^(n)(x_(i)-barx) is (i) -1 (ii) 0 (iii) 1 (iv) n-1

If sum_(i=1)^(5) (x_(i) - 6) = 5 and sum_(i=1)^(5)(x_(i)-6)^(2) = 25 , then the standard deviation of observations

If x_1, x_2, .....x_n are n observations such that sum_(i=1)^n (x_i)^2=400 and sum_(i=1)^n x_i=100 then possible values of n among the following is

If barx represents the mean of n observations x_(1), x_(2),………., x_(n) , then values of Sigma_(i=1)^(n) (x_(i)-barx)