Given r = 0.8, `sum xy = 60`, `sigma_(y) = 2.5` and `sum x^(2) = 90`, find the number of items, where x and y are deviation from their respective means.

Given r=0.8,Sigma xy=60,sigma_(y)=2.5 and Sigmax^(2)=90 , find the number of items, if x and y are deviation from their respective means.

If Cov(x,y) = -2, Sigma y = 30 , Sigma x = 25 and Sigma xy = 140 , find the number of observations .

If sigma_(x) = 3, sigma_(y) = 4 , and b_(xy) = (1)/(3) , then the value of r is

Find the cov (X, Y) between X and Y, if sum u_(1)v_(1) = 55 and n = 11 , where u_(1) and v_(1) are deviation of X and Y series from their respective means.

If n= 12 and sumu_(i)v_(i)= 60 , where u_(i)" and "v_(i) are deviations of X and Y series from their respective means, then cov(X, Y) is

Given : (log x)/(log y) = (3)/(2) and log(xy) = 5, find the values of x and y.

If for a distribution sum(x-7)=6 and sum(x-7)^(2)=78 and the total number of items is 12 then mean and standard deviation are (i) barx=7.5,sigma=2.5 (ii) barx=7,sigma=2.5 (iii) barx=7.5,sigma=2 (iv) barx=7,sigma=2

find the sum of coefficient in (x+y)^(8) .

Sum of the squares of deviation from the mean of x series is 136 and that of y series is 13. Sum of the product of the deviations of x and y series from their respective means is 122. Find the Pearson's coefficient of correlation.

If for a distribution sum(x-5)=3,sum(x-5)^(2)=43 and the total number of terms is 18 then mean and variance are