Hello all! I have a homework problem (THAT I HAVE ALREADY WORKED OUT...for those of you who might think that I am simply looking for quick answers and not doing my homework...)

One of the Hawaiian volcanoes is 30,000 feet high, and has a volume of 10,000 cubic miles. Assuming that the volcano is shaped like a cone with a circular base, find the distance around the base of the volcano.

I know that I need to find the radius of the volcano, then compute the circumfrence....i just do not know if my math is right along the way. I set the volume of 10000 cubic miles equal to the equation for the volume of a cone. I then converted the height to miles, and found the radius to be about 41 miles, so I got the distance around the base of the volcano to be 82*pi miles.

I would appreciate any insight or confirmation that you may have to offer.

Thanks!