Official Guide Explanation:
Data Sufficiency #17




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Solution and Metadata

Question: 17
Page: 274
Difficulty: 4 (Moderately Easy)
Category 1: Arithmetic > Properties of Integers > Evens and Odds

Explanation: Simplify each of the statements.

Statement (1) is sufficient. The sum of the three expressions is 3P + 15. Simplify:

3P + 15 = even

3P = even - 15

3P = odd

Since P is an integer, the only way 3P can be odd is if P is odd.

Statement (2) is also sufficient. The sum of these three expressions is 3P + 8. Simplify:

3P + 8 = odd

3P = odd - 8

3P = odd

By the same reasoning as in (1), P must be odd. Choice (D) is correct.

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