Identify the numbers that occur in the series 0, 7, 26, 63, 124, ... Choose the correct answer from the options given below.

1.344

2.511

3.215

4.730

A1 and 2 only

B2 and 3 only ✓ Correct

C3 and 4 only

D1 and 4 only

Correct answer: (B) 2 and 3 only

Explanation

The numbers 511 and 215 occur in the series.

Each term follows n^3 - 1: 1-1, 8-1, 27-1, 64-1, 125-1.

511 = 8^3 - 1 = 512 - 1.

215 = 6^3 - 1 = 216 - 1.

344 and 730 are not of the form n^3 - 1.

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