If the mean of observations x,x+2,x+4,x+6,x+8 is11,find: 1) the value of x; 2) the mean of first three observations. Share with your friends Share 0 Prakash Dwivedi answered this May this help u 0 View Full Answer Prakash Dwivedi answered this There is pic of answer 0 Prakash Dwivedi answered this Pic isnt going 0 Prakash Dwivedi answered this x+x+2+x+4+x+6+x+8/5=11 theefore adding all we get 5x+20/5=11 = x+ 4 = 11 = x = 7 now putiing value of in i , ii and iii 7+ 9 + 11/3 = 27/3= 9 there meano of first three = 9 and x = 7. Formula used = sum of all observation / total no of observation 0