Find the odd number out in the sequence: 8, 27, 64, 100, 125, 216, 343.

Difficulty: Easy

Correct Answer: 100

Explanation:

Problem restatementAmong 8, 27, 64, 100, 125, 216, 343, pick the single term that does not share the same core property.

Given data

  • Sequence: 8, 27, 64, 100, 125, 216, 343
  • Task: Find the unique outlier.

Concept / ApproachCheck for perfect powers. These look like cubes around small integers.

Step-by-step validation 8 = 23 (cube) 27 = 33 (cube) 64 = 43 (cube) 100 ≠ n3 for integer n (not a cube) 125 = 53 (cube) 216 = 63 (cube) 343 = 73 (cube)

Every term is a perfect cube except 100.

Verification / AlternativeNearest cubes around 100 are 43 = 64 and 53 = 125; 100 lies between them and is not a cube.

Common pitfalls

  • Seeing 100 as a perfect square (102) and assuming all are squares—several terms are not squares but are cubes.

Final Answer100

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