Question

The average of 'n' number of observations is given as 5. If the sum of all observations is 20, what is the value of n?

• A.
  2
• B.
  4
• C.
  6
• D.
  8

Answer 1

The correct option is B

4
We know, the Average of n observations is given by:

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

Given,
Sum of all observations = 20
Average = 5
Total number of observations = n

$\therefore$
$5=\frac{20}{n}$

$\Rightarrow$ $n=4$