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1981 AMC 12 Question 27

AMC12 · 1981 AMC 12

Question 27

In the adjoining figure triangle $ABC$ is inscribed in a circle. Point $D$ lies on $\overset{\frown}{AC}$ with $\overset{\frown}{DC}=30^\circ,$ and point $G$ lies on $\overset{\frown}{BA}$ with $\overset{\frown}{BG}\gt\overset{\frown}{GA}.$ Side $AB$ and side $AC$ each have length equal to the length of chord $DG,$ and $\angle CAB=30^\circ.$ Chord $DG$ intersects sides $AC$ and $AB$ at $E$ and $F,$ respectively. The ratio of the area of $\triangle AFE$ to the area of $\triangle ABC$ is

Question illustration
  1. $\frac{2-\sqrt3}{3}$
  2. $\frac{2\sqrt3-3}{3}$
  3. $7\sqrt3-12$
  4. $3\sqrt3-5$
  5. $\frac{9-5\sqrt3}{3}$