Correct answer: 6050. The nth term is 2n × n² = 2n³, so the sum is 2(1³ + 2³ + … + 10³) = 2 × 55² = 2 × 3025 = 6050.
Background: Each term has the form (2n) × n² = 2n³, so the series is 2(1³ + 2³ + … + 10³).
- 5060: 5060 does not match the computed sum.
- 4080: 4080 does not match the computed sum.
- 3050: 3050 does not match the computed sum.
Did you know? The sum of the first n cubes equals the square of the sum of the first n numbers: [n(n + 1) ÷ 2]².
Memory trick: Sum of cubes = (sum of numbers)², then multiply by 2.
Is this answer helpful and correct?
0 agree0 disagree