Sum of the cubes of first 20 natural numbers is ______

Question

Question

This question was previously asked in

TSPSC VRO 2018 Official Paper

Answer 1

Given:

Sum of the cubes of the first 20 natural numbers

Formula used:

\( S = \left(\dfrac{n(n+1)}{2}\right)^2 \)

Where, n = 20

Calculation:

\( S = \left(\dfrac{20 \times 21}{2}\right)^2 \)

⇒ \( S = (10 \times 21)^2 \)

⇒ \( S = 210^2 \)

⇒ \( S = 44100 \)

∴ The sum of the cubes of the first 20 natural numbers is 44100.