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

A circular park of radius 20m is situated in a colony. Three boys Ankur, Syed and David are sitting at equal distance on its boundary each having a toy telephone in his 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, the triangle is equilateral
`ADbotBC` is drawn.
AD is the median of `triangleABC` and it passes through center O.
O is the centroid of the `triangleABC`, OA is the radius of the triangle.
`OA=2/3AD`
Let the side of a triangle a metres then `BD = a/2 m`.
By pythagoras theorem
...
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