The average of the first five multiples of 3 is:

Correct option is A

Given:
Find the first five multiples of 3
Concept Used:
​$$\text{Average} = \frac{\text{Sum of Observations}}{\text{Number of Observations}}$$​​
Solution:
First five multiple of 3 are
3 × 1 = 3
3 × 2 = 6
3 × 3 = 9
3 × 4 = 12
and 3 × 5 = 15
Average of first five multiples of 3 are $$\frac{3 + 6 + 9 + 12 + 15}{5} = 9$$​​
∴ The average of first five multiples of 3 is 9.