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2021 AMC 12A Question 24

AMC12 · 2021 AMC 12A

Question 24

Semicircle $\Gamma$ has diameter $AB$ of length $14.$ Circle $\Omega$ lies tangent to $AB$ at a point $P$ and intersects $\Gamma$ at points $Q$ and $R.$ If $QR = 3\sqrt3$ and $\angle QPR = 60^\circ,$ then the area of $\triangle PQR$ is $\dfrac{a\sqrt b}{c},$ where $a$ and $c$ are relatively prime positive integers and $b$ is a positive integer not divisible by the square of any prime. What is $a + b + c?$
  1. $110$
  2. $114$
  3. $118$
  4. $122$
  5. $126$