Official Guide Explanation:
Data Sufficiency #130




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Solution and Metadata

Question: 130
Page: 284
Difficulty: 5 (Moderate)
Category 1: Word Problems > Measurement Problems >

Explanation: Word Problems \TEXTsymbol{ > } Measurement Problems \TEXTsymbol{ > }

Explanation: Statement (1) gives you a range of possible appointment times. The earliest it could be is Monday at 12:00 AM + 60 hours; the latest is Monday at 11:59 PM + 60 hours. Since 60 hours is two full days plus 12 hours, the first one is Wednesday at 12:00PM, while the second is Thursday at 11:59 AM, so the statement is insufficient.

Statement (2) also provides a range, but says nothing about the day. Taken together, there's a more specific range. The latest the appointment could by on Thursday, according to (1), is 11:59 AM. So, if the appointment is no earlier than 1PM, the appointment must be on Wednesday, so the combined statements are sufficient, choice (C).

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