Calculate the average of the cubes of first five natural numbers?


A) 55

B) 65

C) 45

D) 35

Correct Answer:
C) 45

Description for Correct answer:

As per the formula,

Average of the cubes of 1st 'n' natural numbers

= \( \Large \frac{n \left(n+1\right)^{2} }{4} \)

where, n = 5.

Therefore, Required average = \( \Large \frac{5 \left(5+1\right)^{2} }{4} \)

= \( \Large \frac{5 \times 36}{4} = 5 \times 9 = 45 \)


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