Official Guide Explanation:
Data Sufficiency #91

Background

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Solution and Metadata

Question: 91
Page: 280
Difficulty: 4 (Moderately Easy)
Category 1: Geometry > Lines >

Explanation: Statement (1) is insufficient: knowing the length of the entire line doesn't help you compare the lengths of two parts of the line. Statement (2) is also insufficient: the length of AB is irrelevant to the comparison of BC and CD.

Taken together, the statements are still insufficient. Remember that illustrations in Data Sufficiency questions are not drawn to scale, so regardless of AB and CD being equal, CD could be greater or smaller than BC. (E) is the correct answer.

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