Official Guide Explanation:
Data Sufficiency #169




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Solution and Metadata

Question: 169
Page: 288
Difficulty: 5 (Moderate)
Category 1: Arithmetic > Real Numbers >
Category 2: Arithmetic > Powers and Roots of Numbers > Powers
Category 3: Arithmetic > Powers and Roots of Numbers > Roots

Explanation: Statement (1) is insufficient: if n2 is a perfect square, then n is an integer; if not, n is not an integer. Statement (2) is sufficient: if rt[n] = \func{integer}, then n = (\func{integer})2 , and any integer times itself results in an integer. Choice (B) is correct.

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