Number set — pick the odd number out (all others are composite): 4, 6, 8, 9, 10, 11, 12

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Solve this multiple-choice question and choose the correct option.

Accepted Answer

Introduction / Context:This is a property-based odd-one-out question. The simplest distinguishing feature among the listed integers is “prime vs. composite.” Identify the only prime to find the outlier. Given Data / Assumptions: Numbers: 4, 6, 8, 9, 10, 11, 12 Exactly one should be different by a basic number-theory property. Concept / Approach:Check primality. A prime has exactly two positive divisors (1 and itself). Composite numbers have more than two factors. Quickly factor each number to classify it. Step-by-Step Solution: 4 = 22 → composite6 = 23 → composite8 = 222 → composite9 = 33 → composite10 = 25 → composite11 → prime (only 1 and 11 divide 11)12 = 223 → compositeThus 11 is the only prime; all others are composite. Verification / Alternative check: Try any divisibility tests: 11 is not divisible by 2, 3, 5; hence prime in this range. Why Other Options Are Wrong: 4, 6, 8, 9, 10, 12 each has nontrivial factors; none is prime. Common Pitfalls: Mistaking 9 (a perfect square) for prime — it is composite (3*3). Final Answer:11

Number set — pick the odd number out (all others are composite): 4, 6, 8, 9, 10, 11, 12

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