Official Guide Explanation:
Data Sufficiency #20




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Solution and Metadata

Question: 20
Page: 154
Difficulty: 4 (Moderately Easy)
Category 1: Arithmetic > Properties of Integers > Other

Explanation: Statement (1) is insufficient: it gives no indication of the relationship between y and the other variables. Statement (2) is also insufficient: in order for integers to be consecutive, they must be separated by exactly 1, and there's no information here about how far apart the integers are.

Taken together, the statements are sufficient. If z - x = 2, then z is 2 greater than x. If that is the case and x < y < z, there's only one integer between x and z, and that's y. Therefore, x, y, and z are consecutive integers. Choice (C) is correct.

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