Question

if the mean of five observation x, x+2, x+4, x+6, x+8, is 11, find the mean of the first five observations

Answer 1

Step-by-step explanation:

x+x+2+x+4+6+x+8/5=11

5x+ 20/5=11

5x+20=55

5x=55-20=35

x=35/5

x=7

First three observations are x+x+2, x+4, x+6=7+ 7+2, 7+4=7+9+11 /3= 27/3 = 9

So, the 9 is the mean of the first five observations