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Problem 18 (2024 AMC 8)

AMC 8Normal

From module Geometry Basics

Problem

Three concentric circles centered at OO have radii of 11, 22, and 33. Points BB and CC lie on the largest circle. The region between the two smaller circles is shaded, as is the portion of the region between the two larger circles bounded by central angle BOCBOC, as shown in the figure below. Suppose the shaded and unshaded regions are equal in area. What is the measure of BOC\angle BOC in degrees? [See figure in original PDF]

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