Choose the odd number: 27, 64, and 125 are perfect cubes (3^3, 4^3, 5^3). One number is not a perfect cube. Identify the non-cube.

Difficulty: Easy

Correct Answer: 384

Explanation:


Introduction / Context:
Recognizing perfect cubes is a common categorization task.


Given Data / Assumptions:

  • 27 = 3^3, 64 = 4^3, 125 = 5^3.
  • 384 = ?


Concept / Approach:
Compare each entry to nearby cubes or factorize to check whether all prime exponents are multiples of 3.


Step-by-Step Solution:

27 → perfect cube.64 → perfect cube.125 → perfect cube.384 = 2^7 * 3 (not all exponents multiples of 3) → not a cube.


Verification / Alternative check:
Locate 7^3 = 343 and 8^3 = 512; 384 lies between them and is neither.


Why Other Options Are Wrong:
They equal exact cubes.


Common Pitfalls:
Assuming “even and large” implies a cube; exact equality to n^3 is required.


Final Answer:
384 is the non-cube.

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