Question

if the mean of five observations x,x+2,x+4,x+6 and x+8 is 13 find the value .

Answer 1

mean = sum of observation / no of observation.
13= (x+x+2+x+4+x+6+x+8)/5
13= 5x + 20/5
13= x+4
x = 13-4
x= 9

Answer 2

( x + x+2+x+4+x+6+x+8) / 5 = 13

5x + 20= 65
5x = 45
x = 9