Answer:
20 units
Explanation:
You want the diameter of a right circular cone with a height of 21 units and a volume of 700π cubic units.
Volume
The formula for the volume of a cone is ...
V =1/3πr²h
The radius (r) is half the diameter (d), so the formula can be written as ...
V = 1/3π(d/2)²h = (π/12)d²h
Application
Substituting the given values, we can solve for d:
700π = (π/12)d²(21)
400 = d² . . . . . . . . . . . multiply by 12/(21π)
20 = d . . . . . . . . . take the square root
The diameter of the cone is 20 units.