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A circular park of radius 20m is situat...

A circular park of radius 20m is situated in a colony. Three boys Ankur, Syed andDavid are sitting at equal distance on its boundary each having a toy telephone inhis hands to talk each other. Find the length of the string of each phone.

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The positions of Ankur, Syed and David are represented as `A`, `B` and `C` respectively.
As they are sitting at equal distances, then triangle is equilateral.
`AD` is the median of `/_\ABC` and it passes through the centre `O`.
`O` is the centroid of the `/_\ABC`. `OA` is the radius of the triangle.
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