Find the average of the square of first 5 consecutive odd numbers starting from 1 to 9, where the last odd number is 9.

Question: Find the average of the square of first 5 consecutive odd numbers starting from 1 to 9, where the last odd number is 9.

Solution:
The average of square of first n consecutive odd numbers starting from 1 to X, where the last odd number is X, is given by = X(X + 2)/3
Here,
X=9
So, average = 9(9 + 2)/3
= (9 × 11)/3
= 99/3
= 33