The diameter of the given circle is the hypothenus of the inscribed triangle.
The hypothenus of the inscribed triangle is obtained by taking the square root of the sum of the squares of the other two legs.
i.e. Hypothenus = sqrt(30^2 + 16^2) = sqrt(900 + 256) = sqrt(1156) = 34
Thus, the diameter of the circle is 34 yards.
The circumference of a circle is given by 2 x pi x r = pi x diameter
Therefore, the exact circumference of the circle = 34pi yards.