Official Guide Explanation:
Data Sufficiency #12




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Solution and Metadata

Question: 12
Page: 273
Difficulty: 4 (Moderately Easy)
Category 1: Arithmetic > Properties of Integers > Evens and Odds

Explanation: The sum of two integers is even if both integers are even or both integers are odd. Statement (1) is insufficient because it doesn't tell us whether i is even or odd, or anything about j. Statement (2) is sufficient: if i = j, then they are either both even or both odd. In either case, i + j is even, so the correct choice is (B).

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