The Brainliest Answer!
  • qais
  • Content Quality

This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
As the three friends sitting at equal distance , that means the string form an equilateral triangle and the center of circle is the centroid of the triangle.
Let the side of the equilateral triangle be a units
then, by pythagoras theorem ,
the length perpendicular = a√3/2
and centroid divides the perpendicular in 2 :1 ratio.
so, radius = 2a√3/6
⇒20 = a/√3
a = 20√3 m
length of string = 3× 20√3 = 60√3 m
                                          = 103.92 m 
1 5 1