Official Guide Explanation:
Data Sufficiency #58




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Solution and Metadata

Question: 58
Page: 157
Difficulty: 5 (Moderate)
Category 1: Geometry > Circles > other
Category 2: Geometry > Lines >

Explanation: To find the radius of the circle, you need some other measurement from the circle, such as circumference or area. Statement (1) is insufficient: it offers a ratio, but no number. Statement (2) is also insufficient: it provides information about chord AB, but no numbers.

Taken together, the statements are still insufficient. Without a number for some measurement in the diagram, there is no way to find the radius of the circle. (E) is the correct choice.

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