Find the radius of a cone when the surface area is 6pi in^2 and the height is 4".

Question

mayankdevnani · Answer

right cone...yes or no

mayankdevnani · Answer

@tymiller

mayankdevnani · Answer

Surface = Pi*r^2 + Pi*r* sqrt (r^2+s^2)

anonymous · Answer

it doesnt say it just says conical paper cup

anonymous · Answer

here is the exact wording of the problem: A conical paper cup is to have a height of 4 inches. Find the radius r of the cone that will result in a surface area of 6π in2.

anonymous · Answer

The surface area is pi*radius*height. Plug in the numbers.

amistre64 · Answer

conical paper sup; does the surface area include the inside of the cup as well?

amistre64 · Answer

|dw:1347392323875:dw|

amistre64 · Answer

http://math.about.com/od/formulas/ss/surfaceareavol_2.htm surface area is$$\pi r (s+r)$$ lateral area is$$\pi rs$$

anonymous · Answer

Strictly they should also have said slant height (s) but I think its reasonable to assume that's what they meant here (else it's a bit messy).