Home » Aptitude » Numbers

Evaluate 1^2 + 2^2 + 3^2 + … + 10^2.

Difficulty: Easy

Correct Answer: 385

Explanation:

Given data

  • Sum S = 1^2 + 2^2 + … + 10^2

Concept / Approach

  • Use the formula: 1^2 + 2^2 + … + n^2 = n(n + 1)(2n + 1)/6

Step-by-step calculation

S = 10 × 11 × 21 / 6= (10 × 11 = 110); 110 × 21 = 23102310 ÷ 6 = 385


Verification

Manual partial sums (1^2+…+5^2 = 55; 6^2+…+10^2 = 330) ⇒ total 385.


Final Answer

Sum = 385.

← Previous Question Next Question→

Discussion & Comments

No comments yet. Be the first to comment!
Join Discussion