geometry

posted by .

A cone has a volume of 36pi cubic meters. Its height is four times its radius. Find the surface area of the cone.

  • geometry -

    v = 1/3 pi * r^2 * h

    h = 4r

    36pi = 1/3 pi * r^2 * 4r = 4/3 pi r^3
    27 = r^3
    r = 3

    If you don't include the area of the base,
    a = pi * rs = pi * r*sqrt(r^2 + h^2)
    = pi * r*sqrt(r^2 + 16r^2)
    = pi * r^2 * sqrt(17)
    = 116.6 m^2

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Geometry

    Can someone please check these for me. I have to leave answers in Pi. Find the Volume of a right cone with radius 6 height 10 V=1/3 pi r squared*h =1/3pi (6)^2(10) =1/3(360)pi =120pi Find the volume of a sphere with radius 3cm V=4/3 …
  2. geometry

    The surface area of a cone is 38 in^2. The radius of a similar cone is triple the radiusof the orginal cone. What is the surface area of the new cone?
  3. geometry

    Two cones are similar. The larger cone, R, has a volume of 1331 cubic feet and the smaller cone, S, has a volume of 64 cubic feet. Find the scale factor of Cone R to Cone S.
  4. 7th g-math

    An ice-cream shop offers a small size cone and a large size cone. The height of the large cone is 2 times the height of the small cone. The radius of the large cone is 2 times the radius of the small cone. Which statement is true about …
  5. Calculus

    A cone is inscribed in a sphere of radius a, centred at the origin. The height of the cone is x and the radius of the base of the cone is r, as shown in the diagram opposite. Find the height, x, for which the volume of the cone is …
  6. Math

    the formula for the volume of a cone is v=1/3pir^2h. The volume cone x is 2 times the volume of cone Y. Why the height of cone X is 2 times the heigh of the cone Y, and the radius of cone X is the same as the radius of cone Y.
  7. 9th grade geometry

    Rounded to the nearest hundred cubic meters, what is the total capacity (cone and cylinder) of the storage container?
  8. Math

    What is the surface area and volume of a composite figure made up of a hemisphere and a cone in terms of pi?
  9. Geometry

    A cone has diameter 12 and height 9. A cylinder is placed inside the cone so the base of the cylinder is concentric with the base of the cone and the upper base of the cylinder is contained in the surface of the cone. If the volume …
  10. Geometry

    A cone has diameter 12 and height 9. A cylinder is placed inside the cone so the base of the cylinder is concentric with the base of the cone and the upper base of the cylinder is contained in the surface of the cone. If the volume …

More Similar Questions