Question

find the mean of x+1 ,x+3,x+4and x+8

Answer 1

mean= sum of observations/ number of observations
= x+1+x+3+x+4+x+8/4
4x+16/4
4(x+4)/4
x+4 is mean

Answer 2

x +4 is mean as
total number of observation=4,
sum of all observation=
x+1+x+3+x+4+x+8= 4x+16=(x+4)4/4;
in this 4and 4 get cancel thus we are left with x+4 which is mean