[MOVED] Geometry: surf. area of cylndr. topped by hemisphere

[workingmom]

An observatory has the shape of a right circular cylinder topped by a hemisphere. The radius of the cylinder is 8 ft and its altitude measures 26 ft

A. What is the approximate surface area of the observatory? Round to the nearest foot. Show all work to receive full credit. (Hint: Remember the top and bottom of the cylinder will not be painted, so do not include them in your surface area. However, note that the hemispherical dome will be painted.)

B. If 1 gallon of paint covers 300 ft2, how many gallons are needed to paint the surface if it requires three coats? Round up to the nearest gallon. Show all work .

 

[tkhunny]

Re: Geometry

observatory has the shape of a right circular cylinder topped by a hemisphere. The radius of the cylinder is 8 ft and its altitude measures 26 ft

The altitude of the cylinder or the whole observatory?

A. What is the approximate surface area of the observatory? Round to the nearest foot. Show all work to receive full credit. (Hint: Remember the top and bottom of the cylinder will not be painted, so do not include them in your surface area. However, note that the hemispherical dome will be painted.)

Who said anything about paint?

B. If 1 gallon of paint covers 300 ft2, how many gallons are needed to paint the surface if it requires three coats? Round up to the nearest gallon. Show all work .

Lateral Surface Area of Right Circular Cylinder = \(\displaystyle 2\pi r h\)

Surface Area of Sphere = \(\displaystyle 4\pi r^{2}\)