Official Guide Explanation:
Data Sufficiency #171




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Solution and Metadata

Question: 171
Page: 288
Difficulty: 6 (Moderately Difficult)
Category 1: Arithmetic > Properties of Integers > Remainder
Category 2: Arithmetic > Real Numbers >

Explanation: Statement (1) is sufficient: if x divided by 100 has a remainder of 30, x must be some multiple of 100 plus 30, such as 130, 230, 530, or 4,430--in all cases, the tens digit is 3. Statement (2) is insufficient: if x divided by 110 has a remainder of 30, x must be some multiple of 110 plus 30, such as 140, 250, or 360, which opens up the possibility for several different tens digits.

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