Discuss the below:
Q: Let four random variables X1, X2, X3, X4 have common mean m1=m2=m3=m4= 5 and common variance (sigma 1)^2= (sigma 2)^2= (sigma 3)^2= (sigma4)^2= 6 and common correlation coefficient p(sub ij)= .1, i does not equal j. Determine the mean and the variance of Y=X1 +X2 + X3 + X4