Your question is missing information about the height of the cone. However, I will try to help you with the concept.
The volume of the cone can be calculated as follows:
volume = [tex] \frac{1}{3} \pi r^2h[/tex]
where:
π is a constant = 3.14
r is the radius of the cone
h is the height of the cone
To get the radius, we need to have information about both the volume and the height in order to be able to substitute in the equation and solve for r
Examples:
volume = 7259.68 yd³ and height = 12 yd
7259.68 = [tex] \frac{1}{3} * 3.14 * r^2 * 12[/tex]
r² = 578
r = 17√2 yd
volume = 7259.68 yd³ and height = 3r yd
7259.68 = [tex] \frac{1}{3} * 3.14 * r^2 * 3r \\ 3.14r^3[/tex]
r³ = 2312
r = 13.22297 yd
Hope this helps :)