An equilateral triangle \(\mathrm{ABC}\) is inscribed in a circle of radius \(20 \sqrt{3} \mathrm{~cm}\). What is the length of the side of the triangle ?

For an equilateral triangle, side = R x sqrt(3) = 20sqrt(3) x sqrt(3) = 60 cm. This follows because the circumradius of an equilateral triangle of side s is s/sqrt(3). A side of 30 cm is only half the true value, the slip of taking s = R x sqrt(3)/2.