Because
The sample mean is the average of n, not an infinite number of observations.
and it's THEOREM
Hi guys i am trying to solve the following theorem
Theorem : If constitute the random sample from an infinite population with the mean and variance , then
and
Solution: Let
Let and as therefore substituting these terms in the above equation we get
Now after this in the book it shows this step
= ...............How did he get 'n' instead of