Question

Consider the following observations:

1,2,3,4,5

We know their average is 3. If I increase each observation by a value of 1; what will happen to the average?

• A.
  It will decrease by 1
• B.
  It will increase by 0.2
• C.
  It will increase by 1
• D.
  It remains the same

Answer 1

The correct option is C

It will increase by 1
If each observation is increased by 1, the new observations are:
2,3,4,5,6.

Therefore,
$Average=\frac{Sumofallobservations}{Totalnumberofobservations}$

$Average=\frac{2+3+4+5+6}{5}$

$Average=4$

Therefore, the new average is 4 which is 1 more than the old average i.e 3

Hence, required answer is (c)