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UKMT Senior Mathematical Challenge, 2024

Geometry Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

The diagram shows two concentric circles divided by radial lines into 14 pieces of equal area. The radius of the smaller circle is 1. What is the length, $x$ , of an outer radial line?

(A) $\sqrt{14}-1$ (B) $\sqrt{14}-2$ (C) $\frac{\sqrt{14}}{2}-1$ (D) $\frac{\sqrt{14}}{2}-2$ (E) $\frac{\sqrt{14}-1}{2}$

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