Question

find the mean of x+77, x+7, x+5, x+3, x-2

Answer 1

no. of observations = 5
we should add all of them = 5x + 90
we should divide it by 5= 5x + 90/5 = x + 18 is the average

Answer 2

 Mean =  $\frac{x+77 + x+7 + x+5 + x+3 + x-2}{5}$
Mean = $\frac{5x+90}{5}$
Mean = x+18