Numbers - Arithmetic Aptitude Questions and Answers

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(112 + 122 + 132 + ... + 202) = ?the smallest whole number in place of * will be:

385

2485

2870

3255

Answer : Option B

Explanation :

(11²+ 12² + 13² + ... + 20²) = (1² + 2² + 3² + ... + 20²) - (1² + 2² + 3² + ... + 10²)

= \(( \frac { 20 \times21 \times41} { 6 } - \frac { 10 \times11 \times 21} { 6 } ) \)

= (2870 - 385)

= 2485.

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