If mean of 5 observations x , x+2 , x+4 , x+6 , x+8 is 11.
Find the median of first three observations.
The given observations are x, x + 2, x + 4, x + 6 and x + 8.
∴ First three observations are 7, 9 and 11.
Thus, the median of first three observation is 9.