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Ducks running laps

Source:

April 26, 2022

Problem Statement

Let AB\overline{AB} be a line segment of length 2, C1C_1 be the circle with diameter AB\overline{AB}, C0C_0 be the circle with radius 2 externally tangent to C1C_1 at AA, and C2C_2 be the circle with radius 3 externally tangent to C1C_1 at BB. Duck D1D_1 is located at point BB, Duck D2D_2 is located on C2C_2, 270 degrees counterclockwise from BB, and Duck D0D_0 is located on C0C_0, 270 degrees counterclockwise from AA. At the same time, the ducks all start running counterclockwise around their corresponding circles, with each duck taking the same amount of time to complete a full lap around its circle. When the 3 ducks are first collinear, the distance between D0D_0 and D2D_2 can be expressed as pqp\sqrt{q}. Find p+qp+q.
2022 CCA Math Bonanza Individual Round #10