Let be the mean of x 1 , x 2 , …., x n and be the mean of y 1 , y 2 , …y n . If is the mean of x 1 , x 2 , …., x n , y 1 , y 2 …, y n , then = ?

Question

Philoid · Accepted Answer

(given)..............(i)

(given)..............(ii)

Now, their combined mean is,

From equation (i) and eq.(ii)..

= )