Official Guide Explanation:
Data Sufficiency #115

 

 

Background

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Solution and Metadata

Question: 115
Page: 161
Difficulty: 5 (Moderate)
Category 1: Arithmetic > Properties of Integers > Factors and Multiples

Explanation: Statement (1) is insufficient: if n is a multiple of 4, it could be 12 (not a multiple of 24) or 48 (a multiple of 24). Statement (2) is also insufficient: if n is a multiple of 6, it could be 12 (not a multiple of 24) or 48 (a multiple of 24).

Taken together, the statements are still insufficient. The least common multiple of 4 and 6 is 12, so the statements together imply that n must be a multiple of 12. If n is a multiple of 12, it might be a multiple of 24, but it's not a sure thing. Choice (E) is correct.

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