what is the base of this rectangle?

A rectangle and a triangle are equal in area and also equal in height. If the base of the triangle is 40, what is the base of the rectangle?

find that radius

A cone has an altitude of 40. the volume of that cone equals the volume of a sphere. If their radii are equal, how do I find that radius.

Volume and Density

A hollow steel shaft 12 feet long has an outside diameter of 16in. the inside diameter is 9 inches. What is the weight of this shaft if the steel weighs 0.29 lbs per cubic inch?

volume

A right triangle with legs of 5 and 12 is rotated about it's hypotenuse to form a solid which is pointed at two ends. What is the volume of that solid? (Exactly in terms of pie).

How long is the edge of a cube whose total area is numerically equal to it's volume?

How long is the edge of a cube whose total area is numerically equal to it's volume?