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2025 AMC 12A Question 14

AMC12 · 2025 AMC 12A

Question 14

Points $F,$ $G,$ and $H$ are collinear with $G$ between $F$ and $H.$ The ellipse with foci at $G$ and $H$ is internally tangent to the ellipse with foci at $F$ and $G,$ as shown below.

Question illustration

The two ellipses have the same eccentricity $e,$ and the ratio of their areas is $2025.$ (Recall that the eccentricity of an ellipse is $e = \dfrac{c}{a},$ where $c$ is the distance from the center to a focus, and $2a$ is the length of the major axis.) What is $e?$
  1. $\dfrac{3}{5}$
  2. $\dfrac{16}{25}$
  3. $\dfrac{4}{5}$
  4. $\dfrac{22}{23}$
  5. $\dfrac{44}{45}$