Odd One Out — Among 17, 27, 29, and 37, identify the single value that differs in primality or special form; justify your choice.

Difficulty: Easy

Correct Answer: 27

Explanation:

Introduction / Context:This question evaluates recognition of prime numbers versus non-prime special forms. You must detect which one does not share the basic prime property with the others.

Given Data / Assumptions:

  • Numbers: 17, 27, 29, 37.
  • Prime definition: exactly two positive divisors.
  • 27 is a known cube candidate since 3^3 = 27.

Concept / Approach:First check primality; then check perfect power status.

Step-by-Step Solution:17: prime.29: prime.37: prime.27: equals 3^3, not prime.Therefore, three primes vs one cube composite.

Verification / Alternative check:Try dividing 27 by small primes: 27 = 3 * 9 confirms compositeness.

Why Other Options Are Wrong:

  • 17: Prime; matches the majority class.
  • 29: Prime; matches the majority class.
  • 37: Prime; matches the majority class.

Common Pitfalls:Assuming 27 is prime because it is odd; oddness does not imply primality.

Final Answer:27

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