Question

34) 38) If the Mean of the
observations: X, X+3, X+5, X+7,
X+10 is 9, the mean of the last
three observation is
a) 10.6
b) 10.3
c) 11.3
d) 11.6​

Answer 1

Answer:

c, 11.3

Step-by-step explanation:

mean of 5 observation is 9

ie,( 5x + 25)/5=9

5x+25=45

5x=45-25=20

x=20/5=4

now, mean of last 3 is

( 3x+22)/3=(3×4+22)/3 =(12+22)/3 =34/3=11.3