Official Guide Explanation:
Data Sufficiency #92

Background

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Solution and Metadata

Question: 92
Page: 159
Difficulty: 5 (Moderate)
Category 1: Arithmetic > Properties of Integers > Factors and Multiples

Explanation: Statement (1) is insufficient: if x is divisible by 12, x could be 12 (not divisible by 36) or 72 (divisible by 36). Statement (2) is also insufficient: if x is divisible by 9, x could be 9 (not divisible by 36) or 72 (divisible by 36).

Taken together, the statements are sufficient. If x is divisible by both 12 and 9, it's divisible by the least common multiple of 12 and 9: 36. Choice (C) is correct.

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